They didn’t remove it. They just ended updates for it so you couldn’t also use an updated console AND have linux support. Software isn’t free, so I people are over entitled if they expect lifetime updates.
Which crippled the console, because you couldn't play games online without updating. And if that wasn't bad enough, soon after you couldn't even play new games offline. I used my PS3 as a backup computer when I was at school (came in handy when my laptop died), so I didn't update it. When I bought Dark Souls, I found out I couldn't play it.
This makes sense. New games could rely on API changes in software. It happens all the time for me as an iOS developer, and we have to make an educated decision on which OS versions to support and which ones not to.