I was thinking risky in terms of cost/benefit.
The cost for me to give a fake email is very close to 0, and the risk of getting spam emails or who knows what is much higher in comparison so why bother giving anyone my real email address? I mean I do give it out from time to time (you can easily find it if you want) I’m just speaking generally.
I usually have no problem using my email address to sign up for things. And yes, I do know that emails will come.
Sometimes they are actually useful and I keep them. Often, I don't care and I just unsubscribe. I some not-so-common cases, it is spam, in which case I mark it as such and I am never bothered by it again.
Sure, it's a bit of extra work. But I would not classify it as risky business.