I live in Moscow. There's plenty of Americans and other Westerners visiting here regularly for business or tourism with no problems. Just don't try to smuggle any weed in, Americans keep getting into trouble for that.
Yeah, there's one less than 5 minutes from my flat, and I live a little outside of the centre. I've used crypto very little in recent years, so not a lot of personal experience to share, but I know some people who use them (or just the P2P market places of sites like Binance).
I suspect the ATMs will give you a worse exchange rate than what you'd get on a P2P exchange online.
What's unclear? Most Americans are fine in Russia; the exceptions are unpleasant. I wouldn't worry too much as a nobody, but if I had any sort of high profile, Russia has plenty of motivations to play the tit-for-tat game right now.