I've occassionally played some Dota2 before but I'll be mainly switching to Dota2 after League releases their kernel level anticheat. I mostly play on arch linux (the league of linux community is the best), and I love that Dota2 supports linux natively while I have to literally hack my system and, in the past, patched some binaries to ensure that league barely works on my system. I'd often have the game crash on me right before the game starts because League's spaghetti code can't handle my system.
Overall, I feel like Dota2 is the better game holistically. The UI is better polished, the gameplay is more well balanced, and it doesn't feel like a shithole like League feels like now. I have long been contemplating making the switch, and I feel stupid at this point sticking to League up until they literally kick me out of their game because they want to require a kernel-level anticheat (aka spyware) that will block me from playing on my linux system.
I grew up playing League and I'll miss it, but I love MOBAs and Dotas is the de-facto best there is. My relationship with League can best be described as Stockholm Syndrome at this point, and I'm happy they're releasing me.