I grew up in France and tipping in restaurants was definitely a thing, albeit on an entirely different scale than in the US.

Leaving a few francs (I'm not young) was common practice.

With cash payments growing more rare, and without the ability to tip easily with cards, maybe it became much less common.

That said, I don't disagree with your comment on how it's spreading. What I don't love about the terminals asking for tips is that, IMO, it creates an expectation of tipping that wasn't there before.

Now, in Portugal, we're starting to see cases of "here's the price with a 3€ tip (for example), if you want to pay that", and you awkwardly get to say "no thanks I want to pay the actual price", which I find very unpleasant.

On the other hand, we regularly eat out at a place near us that only takes cash. We usually spend about 18€ and I always leave the extra 2€ as a tip.