Vendors don’t even agree on whether the :gun: is a revolver or an automatic or space ray guns or even water guns, btw it’s an 1911 in original DoCoMo emojis
Sure, that's a benefit of emojis being semantic. If you want 'SFW' emojis, you can get them. Converting them to images makes that impossible. And uses vastly more bandwidth, makes them impossible to copy+paste, probably has accessibility issues, etc.
Same reason why Gmail uses their own emojis rather than the system ones — (as said above) branding. When you send a tweet, Twitter wants it to look identical across all devices. The classic native UI vs cross-platform UI debate in a nutshell.
Cool, so instead of actually serving text, they could also just serve up little SVGs for each letter. Because god forbid the recipient chooses a different font than Gmail!
Twitter is a media between people. Removing emoji representation differences on user devices is a way to hopefully reduce misunderstandings between users.
