Yup, this is exactly my point. It's not the serverless architecture, something you set up on Hetzner yourself with OpenFaaS (https://github.com/openfaas/faas), that is to blame here but the insane pricing scheme for traffic.
Correlation does not imply causation. There is no inherent reason why a serverless architecture would force a provider to have insane high traffic costs, hence it doesn't make sense to put blame on the term "serverless" for that.
On the other hand, if one could explain such causation, then I would be very interested in hearing about it.
Correct, but the effect on the wallet doesn't care if there is a causal relationship. And since my wallet is closer to me than a philosophical debate, the conclusion I reach in this case, is to move my site ;-)