Why was this such a disastrous choice? I enjoyed having the site and with the exception of a couple of heated arguments in the comments, and spam, it was never a concern at all. Even the spam was very minor inconvenience since the filters caught pretty much all of it.
Many of my friends walso ran blogs in the late 2000s to early 2010s and the majority were smaller and had zero arguments in the comments and less spam as well. Just a comment or two on the occasional post.
The blog was the 2nd largest in its niche and lead to me making a TON of friends, one of whom I was later best man for at his wedding. I also ended up getting sweat equity in a business and learning a ton due to that blog. Moderating comments was little to no burden and even if its traffic were 10x more, moderation would still have been a trivial task.
It was a huge success in terms of ROI from my perspective. Having accounts and user-generated content on that site wasn't "betting on myself not to succeed". It enriched my life.
I've built dozens if not hundreds of hobby projects that had accounts. This includes a blog I ran from 2005-2017, flash games in 2010-2011, an ear-trainer for recognizing relative pitches, a couple of apps that do things with photos, half a dozen language learning apps and all kinds of other little projects. In aggregate, having user accounts brought essentially zero concerns other beyond spam management.
Taking payment is a much bigger deal, but even that is something that millions of people do online and the majority haven't even set up a business entity.
Even in China, which is definitely hard mode for established businesses, many hobby projects stay informal and aren't really cracked down on. My first tech job was at a startup in Beijing 11 years ago and we went through some serious hassle to get an ICP and initially just targeted the foreign market due to the lower compliance overhead. That said, none of my personal sites or games were ever blocked, as far as I know of. I knew some friends that built apps on WeChat and got fairly far before formalizing.
Make "user accounts" effectively anonymous. Don't collect email addresses or phone numbers or names. Just use cookies with GUIDs or autogenerated username like the default Reddit ones (without allowing people to put their own name or other PII in). Maybe let the user keep refreshing until they get a random username they don't hate, but it'll end up being something like "Abrasive-teapot-86" and never $walletName or $emailAddress. If you need to let people move accounts between devices/browsers, let them grab their GUID and call it "secret account key" and tell them never to share it. Also let them know there's no such thing as "resetting their password" and to store that secret account key if they want to be able to recover a "lost" account.
You can't _always_ get away with that. But if you can, it saves a lot of headaches.
Now I can do that with Playwright! - Thank you so much.
He built https://keepthescore.co/ precisely with this in mind.
One of my projects was a "squarespace" style page builder. Right away, there were nefarious users. The block editor meant that bots weren't really an issue, they couldn't figure out how to use it, but turns out humans aren't that great either. My country doesn't have safe harbor laws, so I took it offline.
Thinking now, I could put that builder back into service and just have it spit out an HTML/CSS bundle for people to self host.
I'm currently working on my first-ever side project with user accounts, and now I'm wondering what I'm in for. :-)
Why's that? Can't you just provide the service as-is? I have a project that has user accounts and when people ask me for features or support, I either don't respond or say that it's not my focus.
I have created https://kyselo.eu/ which is social network for refugees of now-defunct Soup.io.
If your project has user accounts, you'll get users who you have to take responsibility for. Then it's not a side-project any more, it's a part-time job.
These days I much prefer side projects which have no user accounts at all (like https://www.niche-museums.com/) or that are open source tools where the end user installs and uses the software without me having any involvement at all (like https://github.com/simonw/shot-scraper)