I’ve been avoiding Nvidia for a while and I generally recommend it (at least for now). I wouldn’t say it’s mandatory though. Nvidia support has come a long way.
That being said, if you can snag a good used amd card to replace your 3060ti then why not if you’re not benefiting from the rtx features and you find your current vram is causing issues, then you do you.
You could also hold out a bit longer and see if the 6800xt becomes more affordable given the recent launch of the mid tier 7000series.