Its not as extreme as that. You dont lose all of your hair when you take steroids. Even people with bad hairloss dont go bald after a few cycles.
You answered the question yourself. Why would anyone who has hairloss, take steroids? If not taking steroids was an option for me/us, then we wouldnt take them. We still do, which means that being muscular makes us happier than hair. Personally for me, being jacked is way too great for my entire life to simply ignore it. And losing a bit of hair for such a big improvement of my life and well-being is totally worth it for me.
Some people just do it wrong and wreck their hair. They take substances that are too harsh for hair. Or they take amounts that are too harsh too, and then they dont lift and eat and try to compensate with more steroids, while wrecking more and more of their hair. Sometimes its kinda sad to see the kinda state people are in on PEDs.
If you do it right, keep your dosages low, protect your hair as best as possible, lift and eat enough, you'll end up with minimal hairloss and great gains. That only applies to people who simply want to look jacked and impressive for the normal folk. Obviously if you want to be a bodybuilder you have to take amounts that will wreck your hair no matter what