I find that IG has at LEAST as many ads as FB. I use both regularly; I prefer Facebook because of the "community of friends and family" feel to it, but I'm sure I use it less than I used to. Part of the problem for me was engaging with groups more. They're easier to 'ignore' for a week and not feel like you missed anything, and if your feed is more and more group stuff it's easy to feel like you don't have 'time' for it, where the friends+family stuff beckons to me more.

Twitter is basically complete toxic trash and I don't touch it.