I wonder if proton mail falls in this category?
The problem isn’t your mail service. I have a proton account. I treat incoming email there with the same suspicion I treat it elsewhere.
The problem is scammers sending you emails that look legit and aren’t.
I think my advice is sound regardless of how you receive your email.
That advice also happens to be what I get from my employer’s security department. They like to “test” us by sending surrogate “scam” messages, and they’re pretty good at making them look legit. Between the training and the testing, I’ve gotten pretty good at smelling email bullstuff.