It's not about who reads it, it's about who has access. If a system has access to read my email as plain text, it means anyone who owns or can get access to that system can read my email.

Some one wrote fread, it could've been john, and john absolutely could be reading your email. Look at the what happened with ubers god mode.

That said the value of gmail for me exceeds the risk of people I care about reading my email getting access or having access. However my(and probably your) subjective view on the value of your emails is absolutely subjective.