I see a lot of spam coming from sendgrid, so I wonder how long they can continue operating that way until they get blocked completely by one of the larger mailbox providers.

at least you could keep their reviews so users could at least know if the app can be trusted.

You mean, don’t trust a flatpak uploaded by a random person, but if there are enough fake reviews, it can be trusted?

I still think Ubuntu is the best option (particularly if you want to use the non-LTS releases)

Having said that I do hate snaps and also dislike flatpaks. So what I do is just use the Firefox deb package from the PPA and the chromium package from Linux Mint. Oh, and I have actually replaced ubuntu-advantage-tools with a no-op dummy package.

“secure alternative”? Others are not secure?