I carry what I need to fix most flats. Tools, patch kits, spare tube, air. I haven't had a lot of flats lately. There aren't a lot of natural or man-made flat-causing things in the roads around here, and/or I've been lucky. I suppose if I were having flats a few times every month my attitude would be different, but I don't. When I have a flat, I fix it. If it's the rear tire, I'll see if I can fix it without taking the wheel off. I have a hub motor. If I have to take the wheel off, I do. It just does not seem like that big a deal to me. I have AAA but I can fix a flat and be on my way long before a AAA truck would even show up.
I have tubed tires that I overdose with Slime. I can't tell it's there as far as weight, etc., is concerned. I'm sure with the right scientific instruments you could prove it increases rolling resistance and maybe it takes a few meters off of my range, but I don't notice it. Anyway, tubeless tires are full of sealant too, so that argument for tubeless doesn't amount to anything. (No, they aren't FULL of sealant. I hope you know what i mean.)
TT