Hmm, moving to a free service can take a lot of time, there might be lock-in?
I don't have specific experience of netlify.
I stayed with my hosting provider despite them doubling my costs just because it would take a long time to find another trustable provider with the offering I need and then a lot of time to move and make sure everything is working.
If it's just a white label service then yes, easy to switch back. If it's not directly comparable then integration costs (in time) can mean you've been "dumped in the road half way there".
Of course if the driver tells you directly "I might have to drop you half way" then that's fine.