Disney, MAX, and other uses L1 for 1080p and up. Even if you managed to download a 1080p from Disney, you need L1 keys. If you have an android that has L1 cdm, you can extract it (don't know how). And L1 cdm gets blacklisted after few hours or days. You need another L1.
Streamfab is much easier to use for L3 content. Streamfab emulator can download 10 videos per day, and then use VPN or TMAC to bypass 10 downloads.
Be careful, some people will try to scam you selling you L1 cdm.
Yes, it won't work with L3 keys. As far as I know, L1 is different, you cannot just extract it without hacking it.
I never heard of L2 too so no idea. And yeah, you need physical device for L1. In some cases, you don't actually need the device, but the keys to decrypt the video.