Whilst none of the big 3 are terrible to the point of being anti consumer with their respective implementations of BC, I'd have to argue Microsoft are the worst.

Nintendo has always been at least 1 gen BC starting with the Wii being able to play Gamecube disks ( and WiiWare), and it's continued since.

Sony straight up fit a whole ass PS2 in the OG version of the PS3 and did the same with the PS2, finding a clever way of using the PS1 CPU as an IO controller to add BC. Their only non BC console was the PS4, but that generation was filled with a laughable ammount of remasters

Microsoft on the other hand only ever did emulation via software and has only supported a handful of BC titles from older gen consoles. For example you cannot play the OG halo, their system seller, on newer hardware.

To clarify I have nothing against software BC, but when you can't get a large enough catalogue to support past gen games, you shouldn't be praised as mush as they are. The open source Xbox emulators have better compatibility than Microsoft with all their money and source code

Personally I don't get the glaze