I have been a vegetarian for years, though have recently started experimenting with fish. We don’t have all of the chains you listed here, though, and I’ve never bothered with Joe’s Crab Shack or Outback (I mean, why?).
I avoid most chain restaurants but, on your list, I have found Olive Garden among the most vegetarian-friendly. Eggplant parmesan seems to be a staple, and there are almost always several options. Olive Gardens are my “out of town” staple. When passing through Iowa, there seem to be Olive Gardens on or closely off the interstates in major cities, but finding anything else vegetarian friendly is a challenge. (Dubuque, I’m looking at you. I’m sure there are other things, but, not close to our route.) This also tends to be my go-to chain when with people who insist on chains, since I hate most chains so much. I know it’s not great, but it’s serviceable at least.
Cheesecake Factory has tons of options. I find their dishes kind of a crapshoot overall, but on the occasions I’ve gone there, Evelyn’s Favorite Pasta is a pretty serviceable dish. Stay away from the eggplant sandwich if they still have it - way too greasy! The bread was falling apart from grease. They had Pad Thai at one point, but it doesn’t seem to be on the menu now. Not recommended. Lots of dessert options, of course. I like their house bread that comes with dinner.
Among the worst would be Applebee’s, which you fortunately did not list. I hate the Veggie Patch Pizza and that seems to be the only regular menu item that is vegetarian. They also seem very poor at customizing orders. It’s been a long time but I did not find TGIFriday’s or Chili’s much better, but this was years ago.
Red Lobster is dreadful for vegetarians. The only thing - other than a side salad - I could get there was some kind of lackluster chicken pasta alfredo, minus the chicken. Dreadful.
Surprisingly enough, a little lower on the totem pole, IHOP has lots of vegetarian friendly options. Breakfast food generally is good as it’s easy to order dishes just without bacon or sausage. I love the cheese blintzes.
If you have Village Inn or Red Robin, they have all of their burger options available with a meatless patty, so I don’t mind going there on occasion. (Dry restaurant Gardenburger? No thanks. Add avocados or blue cheese? I’m there.)