I know its a bit difficult to set the site name ended .com domain because almost all names were we thought have been used by others. I have a bit silly question here, did you mean premium domain names are only ended with .com?
I haven't said so. However, that's what it looks like, with good reasons. The most popular and the most extensively used domain extension in the world has been .com. It's has become so popular that even when you're using other extensions, your users may still be typing in the .com version
Premium domain names technically can be a .com, .net, .org, .io, and other nGTLDs. But the only true premium TLD has to be .com. Remember also that not all domain with .com extension are considered premium.
Among the most popular characteristics of premium domains are: Short, Memorable, Pronounceable, Brandable, and Keywords Rich (in some cases).