Since 2.4, many of the 3-month content updates (which are always either good content or at least good-faith mistakes) have introduced mechanics which effectively require more microtransaction purchases (see 2.4, 2.5/3.7, 3.1).
Sure, you can technically play through all the content without microtransactions, but have fun organizing the 159 different maps, 104 essences, 42 (ordinary) currencies, endless cards, and all your actual items with the four default 12x12 tabs. Even then, your best bet for listing items for sale without premium tabs is to use a 3rd-party tool to generate a forum thread.
Not to say that PoE isn't one of the better F2P models out there, but GGG shouldn't get away with pretending to be a small indie studio when they have >100 employees and sold a controlling share to Tencent for >100M NZ$. They have (rightfully earned) one of the best reputations among game developers, but their insistence on selling (what should be) standard game features as $15 microtransactions is absurd.
Looking through the store now, what I would consider to be "mandatory" for someone investing significant time into the game comes out to about $70. The free trial is wonderful though!
If you're going to play this game for a significant amount of time, I think it is only fair that you pay it. The question is then if it's worth $70, which I would guess it is.
My point is not that it makes the game bad, but that it's disingenuous to assert that the microtransactions are purely cosmetic or unnecessary. For my case at least, I would prefer if I could just buy the game for $70 and not have to buy more microtransactions if/when some future patch makes them advantageous.
They support the hell out of their game though. I just started playing again and there's so much new stuff to do.
Weird, I played ~70 hours earlier this year and I couldn't craft more than one item at once.
If you like grind then it's free, if you hate grind and won't spend money the game is bad.
[0]: https://www.dota2.com/international2019/battlepass/
PoE's "micro"transaction system is much closer to a paid mod or DLC model. Yes, they're mostly cosmetic and QoL items for sale, but they certainly don't feel optional if you've ever played any other RPG or loot-heavy game. Like you mentioned, prices are stupid high and there's nothing "micro" when decent cosmetics run $40+ and a single full effects set is $150+.
The main story takes 20-40 hours, and pretty early on you'll almost HAVE to buy additional loot storage. It's a loot heavy game with no easy way to sell loot that doesn't require storing it (no gold or credits), so they're banking on people getting annoyed by their stash system (which really sucks) and purchasing the added storage. Rolling a new character uses that same storage, so you feel the pinch at each playthrough.
And even if you complete the story, store bought armor at level 2 looks infinitely better than anything you can actually earn through skill or play time. I mean, they already sell "supporter packs" with effects/pets/etc you can't buy a la carte or earn, so the whole facade of these cosmetics "paying to support the game" is already cracked.
They also play that game where you have to buy a custom currency (points) in $5 increments and the vast majority of the items are priced at odd increments, so you're almost always leaving money on the table.
They could offer multiple monetization schemes, like an unlock with each expansion to allow earning some variation of the nice skins and additional storage, while still keeping the game F2P (though I'd love to see them lock applying purchased cosmetics behind a level requirement). I'd be happy to pay $60 for the game and $30-40 per expansion, but I'm not going to just start dumping money into a game to get past the artificial stash constraints or rent worthless digital paint jobs.
There are too many sneaky little quirks that just happen to favor spending money for me to feel good about the game.
You touch on the two things that make me hate free to play games. It seeps into the design philosophy in a way that makes the experience worse for everybody because they need to incentivize buying stuff. A lot of people like playing dress-up, but there's no way to do that in PoE without paying crazy amounts of money.
Supporter packs aren't there for value, they are there as a "supporter pack". You buy it to give money to the dev, and you get some cosmetics, as well as most of the price of the pack as premium currency, which you can spend on more cosmetics, or stash tabs. I'd argue that character MTX isn't even worth spending money on given the amount of flashy skills and effects there are, that obscure your character, but that's a different argument.
If you're happy to pay $60 up-front for the game, why not just buy the stash tabs and be happy? $60 buys you more than you'll ever fill up.
As someone who played for ~3 years before dropping a dime on the game, I have to say I don't see the "quirks" other than stash space. The only other incentive is the regular "spend points to get a free box" where everyone just spends the equivalent of $0.50 on a bug to get theirs, using up the leftover points they had.
What can be fair is a shop where you can buy cosmetic items. For me, Guild Wars 2 seems like a fair way to do it. The latest content costs money. Cosmetic items do nothing, but cost money. A few convenience items here and there, but no P2W.
I should run GW1 again, wonder if someone is still on there :P
Which, I believe, is fair enough. I'd prefer they not have convenience items up for sale, but compared to a WoW sub (which also makes you feel guilty when you don't use it) it feels fair and less stressful.
People look at POE and see the $30 wings and complain about the prices, but they ignore the fact that Chris Wilson and GGG have consistently put out excellent content (with a few exceptions) every 3 months since the game came out in ~2011. This is the way to do F2P correctly.