> I'm not referring to Cloudflare
Why would you use a slow provider for a comparison point?
> and your functions have to cold boot
For $5 per month, it looks like you get warm startup always on CloudFlare, which is very fast.
Also: Google surely pay some attention to network delays: serving Kenya from a Mombasa POP is going to be way faster than using some server in the US. I would expect Google to give that some juice.
But it could be luck of the draw that Google's crawler hits your site during a period of low traffic, and your functions have to cold boot. That could impact page rankings, as response times influence those.