I don't work for Microsoft (in fact, I work for a competitor), and I think it's totally reasonable to charge for workflow executions. It's not like they're free to build, operate, and maintain.

Well, they provide it for free for the fee tier. And has been for ages. Perhaps they shouldn’t provide rugpull services if they cannot afford it.

Microsoft pleading poverty doesn't really fly

Nobody's pleading poverty here. It's a reasonable business decision to charge for value, just like the rest of the economy does.