Yes perhaps I should have specified you can't get much cheaper for serverless platforms.
You can certainly run a VPS like that for cheaper, you could probably even beat the raw request numbers from those 1€ a month vps from ovh or similar. The key difference is with cloudflare your site is globally distributed by default, and you get to buy into the whole ecosystem, if you want.
But sometimes you do have clients in both sides of the atlantic and it's nice being able to cut their request times by a few hundred ms "for free". Personally, that's not the main reason I use cloudflare, but it can be handy!
You can certainly run a VPS like that for cheaper, you could probably even beat the raw request numbers from those 1€ a month vps from ovh or similar. The key difference is with cloudflare your site is globally distributed by default, and you get to buy into the whole ecosystem, if you want.