Have you not been checking the news?
The days of ICO mania are over. I'm sure plenty of their operators are going to get giant fines for taking the piss. Anyone thinking of doing it in future had better be as compliant as can be or give up on the idea completely.
Yeah, we'll probably won't see those multi-million ICO's anymore, but the smaller ones will still persist, they won't comply with any regulations because they are very blatant scams and they use fake profiles to not get prosecuted. There's still too much naive noobs around who think that ICO's will drive progress, just the discussions here on topics that cover some recent ICO/ICO ads bans by governments and companies.
Ethereum doesn't need to do much in order to implode, it will happen through the following ways.
- Governments cracking down on ICO's.
- The ICO hype ending.
- Ethereum blockchain growing too large.
- Ethereum to lose the battle and see a rival take over.
Number 3 is the most likely scenario, if it will fail to solve scaling in the next few years, it will severely decline, and at that point the devs might lose faith and switch to other projects. Ethereum will probably prevent this by becoming more centralized, since crypto community clearly doesn't care about it anymore.