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.
If there’s something questionable from a family member or friend, the simple solution is to call them and verify it.
My employer did that too.
If you failed and fell for a phishing email - you got a visit from the IT department.
A dear lady I know just lost her husband 3 months ago. She fell for a bogus email and called the sender. Luckily her daughter caught on. They called the bank and closed accounts that had been opened for years just to ward off losing it all.
Those who prey on the elderly deserve a special place in Hell.