Yes. Unless you have a really good reasons there are safe and portable versions you should use instead.

If you tell the Compiler to be careful and avoid writing c code c++ does not segfault. This is a user error.

You can technically even write Assembler code and compile with gpp.

My Lemmy instance only owns this account, not secondary accounts on separate websites

But why? Just use a password manager instead of tying your identity to a Lemmy instance which you do not control.

Having SSO is reliant on having a single trusted server which has your password instead of you maintaining it yourself. This is just an unnecessary risk.