Alternative to GOOGLE groups shutting down...

https://sci.physics.relativity.narkive.com/

https://rec.arts.tv.narkive.com/

https://soc.culture.irish.narkive.com/

https://narkive.com/

Just add .narkive.com/ to the end of the group you're searching for.

For general everyday sending email you should be using tuta.com encrypted email.
"END TO END ENCRYPTION"

This is not about making money, this is about telling people to use end to end
encryption when sending email. Get off Hotmail and Gmail and other like them as
they're scanning your emails, putting ads in your email account and collecting
data on you. Why do you think they're free, do you think they want to make you
happy?

FREE and premium services: https://tuta.com/

Independent tuta review: https://privacysavvy.com/email/guides/tutanota-guide/