A lot of what people are talking about is the 90% of securities regulation that lives in the information space, regulating what must be disclosed when & to whom, and ensuring people are not deceived en masse by those running an enterprise on their behalf. 2008 was largely one of these crises -- there was fraud in the creation and marketing of mortgage-backed securities, about what was in them and what the risks were. If you have enough of those, and enough big institutions dressing up these terrible securities in even more incomprehensible instruments, big ribbons & glossy materials, and marketing them to retail, then the original fraud is compounded in effect and more and more people start being exposed to it. Imagine there are 200 active Ponzi schemes and you sell a financial product offering 10-20% returns against a background Fed cash rate of effectively zero, and you manage to keep it up by investing in Ponzi after Ponzi, reaping the yield they give and propping them up with VC money when they teeter. If enough of them fail, so do you.
If you think that sounds a lot like 2008, well, yes it is. Fortunately this time it's not gone even close to under the radar. Remember 2008 was built on a much safer financial product. Like, there were a lot of good mortgages in America, and for a while there was a healthy market for packaging them up in bonds, it just turned very sour when the bad mortgages started making up the bulk of new bonds issued to meet huge demand and more was wrung from the sponge in derivative products at the same time. The idea of a collapse was unheard-of; the market had quietly undergone huge changes with only a dozen or something people worldwide really taking notice. We're in here with a thread every few days on HN talking about the possibility of a 2008. That's a difference.
Some of the discussion of crypto regulation is more about the "prudential" side i.e. talking about some crypto entities as if they're deposit-taking institutions (like retail aka commercial banks). That's quite recent, I think it's what you're referring to by "influx of dollars ... back into government" i.e. getting them on the Federal Reserve system, getting deposit insurance, and having to be so heavily scrutinised any crypto CEO would have a heart attack in the first 20 minutes. In 2008, some commercial banks got too far into mortgage securities, failed and got bailed out. Some commercial banks doing deposits & loans got bailed out, and some even got nationalised. That protection mostly just worked as planned. Given the fact of bailouts, the risk of bailouts had to be readjusted, of course, so the new laws were about what commercial banks couldn't invest in. Lehmann was of course an investment bank. The main message is that the root causes of the crisis were not perpetrated by commercial banks, so all the new regulation around them was about trimming the risk of bad securities turning into systemic meltdowns. That's a relevant thing to worry about today but note that actual banks are pretty well protected and not really allowed to freewheel like some did in 2008. If your normal bank is investing your deposits in crypto, I would be surprised.
People worry about Coinbase because it's seen as a kind of commercial bank but not regulated as one, so it (1) gets to freewheel on investments & capital requirements like no other commercial bank in the country, and (2) has no deposit protection for those who use it. So risky twice over. Frankly I don't think Coinbase could survive with its current business model as a regulated bank, same way Uber wouldn't survive if it were forced to compete without favour & VC dried up, so forcing Coinbase to to be might trigger the very collapse being protected against (by stopping it investing in all the schemes that make it money, killing those schemes and causing knock-on), and look kinda bad. It's a tricky one. Maybe if there's enough securities enforcement against the things that are keeping the party going, the fraudulent portions can gracefully collapse on their own and the government won't have to cop the blame for bringing on the death of a pretty popular industry by prudential regulation.