I don't think that was the main issue. Bitcoin's main use as an actual currency was for things like drugs, where the legal system wouldn't be on your side anyway. So lack of chargebacks wasn't an issue anyway.

The bigger issues with BTC is the onboarding problem, limited capacity and rapidly fluctuating exchange rate.

I don't think I said it was the main issue. I agree that it had other problems too, including the ones you name.

But I think you're missing my point. The anonymous, one-shot nature of things made it most appealing to only one set of merchants and one set of customers: people doing crime, and who were therefore most tolerant of the risks.

The onboarding problem is also partly a consequence of this. Because a bitcoin transaction is irreversible, and exchange can't just take a credit card payment and give you bitcoin.

Bitcoin actually DID take off for payments. The issue is it became too popular and the people in charge of it didn't want to extend the block size limit.

I would use Bitcoin to play poker online because the alternative was using Western Union - which is much more of a hassle.

Because of this issue, online poker sites now use Litecoin, BSV, BCH, etc.

See: bovada.lv and other poker sites who still offer their services to US players

It actually did not. I agree that it's useful for certain niche quasi-legal cases, but it poses absolutely no competition to both traditional payment media like credit cards and debit cards or modern options like Venmo and MPesa. It was accepted for a brief period by something like 1% of top internet retailers but it's down to at best a handful.

That's because the network maxed out and they decided to fuck everyone by keeping the block size limit. These things don't happen in a vacuum, Bitcoin lost momentum in a critical period

The block size limit was possibly one factor, but I think there were bigger ones. For example, that it's inconvenient, deflationary, slow, harder to use, riskier, and has a double currency risk amplified by Bitcoin's high price volatility.

It has a positive annual money supply increase, so in a way it's inflationary. If you look at the prices IN Bitcoin of common goods they have also increased by like 2x recently, so it has had inflation recently.

I don't think you can claim it as deflationary overall, but yeah, volatile for sure, riskier as well. But it's not like that's the only currency you take a risk with. When I had a plane ticket refunded to me that was settled in Euros I ate a $50 difference due to conversion fees (which were not refunded to me by Paypal). So currency conversion is a risk anyway.

Slow is also relative, a wire would take several days to come in. If I write you a check it takes a few months to clear, even though the bank will lend you that money before it clears.

And I would claim using those methods of payment is more inconvenient. Credit cards are not exactly equivalents because those funds are lent to you by a bank and you pay them back later.

The equivalent for Bitcoin would be Lightning Network, but it's not really usable right now, if it will ever be. Your channel might be closed after 45 days of not using it and other surprises you will experience if you actually use it.

For smaller payments it's actually better to accept 0 conf BCH payments. It has a feature called double spend proofs where after 3 seconds (the time it takes to enter the mempool of all of the nodes) it can detect whether this transaction is being double-spent

You can still double-spend it, but you need a pool with a decent chunk of mining power of the whole network to help you. So for a $1,000,000 payment it would be worth hacking the network (since you are a big pool operator you need it to be worth your while), but not for a $3 coffee