This is actually very good advice. What amount is too many emails? I have a comunity with roughly 30 users. Is that at risk of getting flagged? I just learned my domain is in some blacklist for being “too new” or something, so I suspect the recommended services will reject my domain. An old domain of mine got suspended from mailjet for no apparent reason. “risk to deliverability of our services” or something.
Sometimes I feel the internet establishment does a lot to discourage the small guy or the new guy from starting their projects, with the excuse of “preventing bad behavior”.