I agree in principle and will use mailto: and tel: links on any project where I have the luxury of doing things properly without worrying about the consequences

I agree in principle and will use mailto: and tel: links on any project where I have the luxury of doing things properly without worrying about the consequences. But at the same time it's not easy to explain to a client that their email link might not work for a sizable portion of their visitors, especially if they've seen solutions that work all the time. I also agree about avoiding unnecessary bloat and this seems like a decent tradeoff. It's just a tiny popup that includes the native option, so you could argue it sits between a plain mailto: link and a full-on contact form with a backend service for sending emails/texts.