Is this really legal?

You might want to read this

https://helpx.adobe.com/ie/genuine/faq.html

I also observe the video says "also Adobe if you're watching please don't take this video down -this is strictly educational - you guys should not do this". What a splendly complex morality it takes to make a video encouraging people to steal so you can make money from adverts, then saying people shouldn't be stealing, and begging Adobe to let you keep playing the game. Wicked!

Absolutely not legal because it's never been free. People often try to convince you that pirate software is legal, because their aim is to get you to install their download. Then they can infect your machine, steal your passwords, empty your bank account, host pornography, hold you to ransom - the usual things.