Honestly, seeing what many home cooked meals look like the first time around, I guess I can see why some don’t want to eat leftovers. Our food is very flavorful and usually just as good the next day.
The only exceptions I can think of would be a full piece of meat (like a steak or something), but that’s a more rare meal in our home. When I do have those types of leftovers they are repurposed into another meal and not eaten microwaved (because yes, that would’ve a yucky texture).

I don't really do this but it's a fine idea. I wouldn't consider it
leftovers to take something out of the freezer and having it again weeks or months since the last time. Neither would DH.
Having different definitions of leftovers may change the responses then. To me, prepping ahead or cooking extra meals would definitely fall under the leftovers category.
Maybe this is why I don’t understand the mentality of never eating leftovers. I definitely agree with you that eating the same thing day after day would get old/gross.
But, on the other hand, I have always done a bunch of baking to have breakfasts and snacks for the kids in the freezer. That way they can have something homemade without me having to get up and cook every morning. To me, this would technically be leftovers even though I froze it immediately after cooking with the intention that it would be consumed later.
Hated leftovers as a kid. Food storage in our house growing up was not appealing. Aluminum foil on top of bowls that food was served from. Butter containers for leftovers that you had to search through-blech. Just grossed me out.
I actually can understand this. I’ve been to people’s homes where food is piled up unwrapped or in reused containers and it did gross me out.
We portion our leftovers out into appetizing looking individual meals that DH usually takes to work for lunches.