YouTube shorts and Instagram reels are a rip-off of TikTok.
Live streams. Twitch is built around them, but you can also do them in YouTube and Instagram.
Stories. I don’t even know who did them first, but now they are identical in Facebook, Instagram, and Whatsapp.
It’s also weird how they try to make whatsapp more than it is meant to be. Everybody uses it to replace texting and that’s it.
I know people that “post” stories on WhatsApp and use it for video conferencing very often. Not my cup of tea, but i think those functions do get used quite often.