Free services are never free. It is only free because someone else is paying.
I don’t use this but “hoping” that someone else will donate is not sustainable for them and unrealistic in the long term.
Maybe they should start charging.
That’s what “free” means. Otherwise, nothing is “free” except maybe sunlight.
(Repost of <https://news.ycombinator.com/item?id=21035982>)
They still need to pay for the servers and bandwidth and fight the abuse by malicious users using the service for bad intentions.