Yes, you should cut toxic people out of your life. That doesn’t mean that every relationship on the planet is toxic and should be avoided. People who get amputation don’t just say “I didn’t even need that arm”. They get prosthetics, they go through physical therapy to try and adapt without the arm.

The difference here is unlike an arm, if a friendship doesn’t work out, you can make new friends. If you prefer being alone, there’s nothing wrong with that, but there’s a big difference between saying “I prefer to be alone” and “all relationships are bad and should be avoided”