This was probably the biggest unsolved issue I had when seeking out a new email provider.
"Switch to this other email provider" is not going to get much of a result from your gmail/outlook-using contacts (especially if money is involved), and wouldn't even solve this issue unless you convert absolutely everyone to, for example, Protonmail. "Hey man can you set up this thing called PGP?" is probably even worse unless your social circle is all technically minded already. Even in a group of "nerds that play video games", I'd be surprised if even half of the group even know what PGP is.
So long as we're stuck with email as we know it today, it really seems like there is just no bolt-on solution that can be used to "fix" it.
"Switch to this other email provider" is not going to get much of a result from your gmail/outlook-using contacts (especially if money is involved), and wouldn't even solve this issue unless you convert absolutely everyone to, for example, Protonmail. "Hey man can you set up this thing called PGP?" is probably even worse unless your social circle is all technically minded already. Even in a group of "nerds that play video games", I'd be surprised if even half of the group even know what PGP is.
So long as we're stuck with email as we know it today, it really seems like there is just no bolt-on solution that can be used to "fix" it.