I've found a lot of people in my generation (Millennial) don't eat red meat, not because they don't want to but because they can't. It gives me incredible heartburn, and many of my friends become physically ill if they eat it.
Tick bites can cause it. Something about your body building immunity to a protein transferred by the tick that closely matches those found in beef or something like that.
Millennial here and I've had a similar experience. I ate a ton of red meat growing up, but once I got to my early-to-mid 30s, I noticed beef would give me a lot of stomach issues. I switched to eating chicken and sometimes (depending on the dish) substituting the meat entirely for black beans and found my stomach issues got a lot better. And it's still just as tasty to me, so I don't feel like I'm missing out on anything.
I’ll usually find that burgers/steaks etc at restaurants are what usually bother me more than if i go and buy/season/cook myself. Not sure if it’s just over seasoned meat, or the type/quality. Even then, I usually prefer chicken or turkey-based (lower fat) alternatives or mixes (like a turkey ground chuck).
I haven’t really gotten into plant-based alternatives, though I’m not opposed to it…as long as it tastes good! Lol
The two go hand in hand. Food service-grade ingredients are notoriously bad and cheap. They then compensate for this by heavily seasoning it so you don't notice how bad it is. In the rare case that a restaurant uses high quality ingredients (e.g. serving prime rib), they are unlikely to season it as heavily.
When I had Celiac undiagnosed, all I could figure out was that I felt awful after meals. My theory was I needed to eat more healthy. I started eating whole and organic foods, which didn't help, then became a vegetarian, which didn't help (and some people sure were dicks about it). But yeah, anything that leads to eating more veggies and fiber can help with certain digestive issues and overall health.