I occasionally get spam replies, but not very often. I just block the account, problem solved. I don't feel it affects my overall Twitter experience much. In fact, I'm vastly more annoyed by real humans who reply to me with insults. Or real human Twitter "influencers" who start quote tweet memes that everyone obsequiously follows, "spamming" my timeline with the same tweet over and over. In other words, IMO the humans are worse than the bots. ;-)
I'm not Twitter famous. I've got several thousand followers, which is significant but not huge. Maybe if you have millions of followers, bot replies are a much bigger problem for you. But then again, if you have millions of followers, nasty real human replies are also a much bigger problem for you. Fame is a no-win scenario, except just ignoring replies entirely.
If you use the reverse chronological timeline, you only see tweets from the people you intentionally follow. (I wouldn't advise anyone to use the algorithmic timeline, unless you're into masochism.) So I literally never see bot spam in my timeline. Spam isn't really affecting me. OTOH I never tweet about "crypto"...