There are many other types of business besides startups, and not all technology businesses are startups. That's fine, many of them work very well. Rapid growth is not the only way to run a successful business. But they're not "startups," by definition, they're some other kind of business.

You can, of course, attempt to appropriate the word "startup," redefine it to mean something else, and then attempt to get others to use your new definition, but empirically it seems that almost everyone is using pg's definition above for that word.