The evidence is not "news articles", but the contents of those articles where a high-ranking prosecutor threatened to go after GrapheneOS "if they don't cooperate with the law".
No matter your feelings about the creator, I think this was entirely the rational choice.
France is pro-Chat Control. For about a year now there's been an anti-drug trafficking fervor among legislators and government, in which they've pushed for encryption backdoors (separate from Chat Control at the EU level) and recently threatened GrapheneOS. The country is politically unstable so future politics are hard to predict, but anti-encryption politicians stand a good chance of winning the next election. Any rational project would move out.
Didn't France intercept Telegram's CEO to force him to backdoor the app while in country?
Yes. Yes they did.
I don't disagree about leaving France over their position on chat control or legislation.
I disagree about them essentially spreading misinformation about what actually happened. One prosecutor, that probably doesn't even know what GrapheneOS is, making boisterous claims to the press, is not the same as being contacted by the state about adding a backdoors.