I'm not on any social media (unless you count reddit and youtube -- where I do not watch skincare content unless I'm specifically looking for info) but I do buy a lot of products on impulse. I'd say my impulse buy thresholds are

• under 15 € -- yeah, sounds good, add to cart
• under 20 € -- I'll read full description, maybe even a review or two
• under 40 € -- whoah, let me do some research, this better be good (and I'll usually buy a mini/another product in the same line first)
• more expensive -- yeah, that better work for me 100% and probably floss my teeth as well

I have bought products that haven't suited me at all (allergic reactions) and products that haven't done anything for me.