Clearly, you’re too nice a person. When a recipe says mix, you stir gently. When it says knead, you give the dough a gentle squeeze or two and move on. Well, guess what? That dough needs working, and you’re just the one to do it!
You’ve really got to exercise the dough to get the gluten going, to stretch it and produce the structure that you need for a great chewy pizza crust. And without the well-developed gluten strands to hold in the carbon dioxide the yeast is so busy producing, no wonder your crust doesn’t rise. Don’t just mix and expect it to take off on its own. This is true for a well-developed bread of any kind, because in the process you allow the flavors of the yeast and wheat to fully develop.
You do need to get a feel for making the dough, so that you work enough flour into it to get the right consistency. (If you’re in the middle of a humid summer, your dough is quite likely to need extra flour to compensate for the moisture in the air.)
If you own a bread machine with a dough setting, you can let it do the work for you, because it will give the dough a great work out. You can also use a food processor, or a large stand mixer with a dough hook. Otherwise, get serious about learning to knead.