IMHO the question isn’t as much you as a user of such platforms is “f*cked” because you sound both mindful and technically savvy. So, on that front, you will be OK.
The harder question I would say is how morally bankrupt you will feel by contributing to worsening the privacy of others for profit. Namely that yes by using Facebook/Insta/TikTok/etc you will gain more customers but those customers are gradually losing their privacy while you make those companies bigger by paying them. That means you depend on those companies more while they get more power.
Because of that I would argue that sure, do everything you can to protect yourself but it can’t stop there. I would argue then than the question is rather, where else can you find more clients, and maybe even “better” clients who are more aligned with your own views on privacy, and maybe even more. It’s definitely a challenge, especially seeing the trend of surveillance capitalism, but as you acknowledge yourself by using Lemmy, there are actual alternatives.
I’d be up for a review on new models, e.g https://kilow.com/pages/la-bagnole from France, which claims to be repairable.