depends on your platform and your level of experience. Both unreal and godot have steep learning curves depending on where you come from. GDevelop is very accessible but also caps out quite fast. Great for making prototypes and getting simple games out there but depending on your level of ambition you will probably outgrow it sooner or later.
This is absolutely mad vendor lock in. I’m doing the maths and if you create the next flappy bird and it goes viral and gets 50 million downloads in a month, you’d owe unity $10 million dollars before you’d even received your first monetization cheque (you did launch with a full monetization plan, right? right? oh.)
edit: i forgot they had moneitzation limits too, so no - this situation wouldn’t quite happen until they earned $200,000 in revenue. Though the potential to go viral and find yourself underwater because of the massive unity bill in comparison to your income is still a possibility
as someone who was reasonably deep with unity, the alternatives really are quite thin - Godot is a big contender or otherwise it’s time to pick up some Rust game development