[muststopmyths]

>If anyone from WhatsApp/Telegram/Signal/etc is reading this, I would pay a lot for a "Pro" account to have high-res photo uploads for my wedding/music festival/travel/etc group chats

Doesn't Telegram allow full-resolution sharing of pictures out of the box ?

Unfortunately, you'll probably get people sharing whichever way they're most comfortable with and have to ask them specifically for originals.

[eitally]

Telegram does allow sharing full-res (both photos and videos)... but you're at the mercy of the end user to select that option at upload time, and I'm not confident this is reasonable.

[bilekas]

Telegram does intact have "lossless" image transfer.. might not be suitable on a mobile device though with space considerations and lack of cloud sync by design.

[dvngnt_]

I think if you choose file, it will share the uncompressed file vs photo from gallery