Off topic but I never got into Gundam as a whole and it's a 50 year old franchise at this point. I loved LOTGH and I wanted to get into Gundam. What's the watching/reading order you'd recommend?
I'm not the best person to ask since I've only recently started getting around to watching any series (despite already having built a few Gunpla). That said, the thing about Gundam is that lots of the series are self-contained in their own timelines, with UC being the timeline with the most content produced for it by far. This means you can pick pretty much any non-UC series at random and give it a whirl without needing a lot of backstory or anything.
If you want to get into UC, I'd suggest starting with the original 1979 series and going from there. Some people find it hard to get into due to its age, and it's certainly rough around the edges, but I find it charming in that way. Yeah, there's dust on the cels and the mecha are frequently off-model, but the story's been engaging enough to me so far that I either don't notice or don't mind. After that, I'd recommend what I recommend for other long-running series: continue to go in release order, not chronological, since prequels/interquels usually rely on your knowledge of the older works to make the most sense; don't forget to watch the various OVAs as well, with War in the Pocket being of particular note. Just remember that quality's going to vary along the way, even within series.
(Note that a lot of the early series have been re-edited along the way into compilation movies that serve as a quicker way to get through their stories. I'd personally steer clear of those and take the time to view the series as originally envisioned.)
The only other timeline stuff I've seen is G Gundam and Iron-Blooded Orphans. I've already discussed my love of G Gundam, but IBO never really grabbed me. I got about halfway through the first season before my interest fell through. I might revisit it at some point, but right now I can't give a recommendation for it.
From my understanding G Gundam was made the way it was because the popularity for the franchise was declining at the time. Both viewership numbers and merchandise sales were dwindling. The sponsors essentially forced the production to do a major reboot of the franchise because they felt what they franchise had been doing was played out by that point.
Fans of Universal Century probably owe more to G Gundam than they realize. It might have been flawed, but it likely did a lot more to save the franchise and renew interest in the Universal Century saga.
I recall reading somewhere the boost in ratings and toy sales - when you have a hundred different Gundam models thats a given - is probably what kept the entire Gundam franchise alive past the 80s.
It did for Gundam what the Thrawn novels did for Star Wars.
I think it's no secret that Gunpla are what saved Gundam from being just another forgotten mecha series; the original show's declining ratings led to its early cancellation, and it was only due to the massive success of the toy sales that caused them to greenlight new series. From what I gather, by the time G Gundam aired, Gundam's popularity was waning some, so they felt a reboot was needed to get people (mostly kids) interested (to buy more toys).
Apparently, their attempt wasn't hugely successful as G Gundam only did slightly better than the previous series Victory Gundam, but it was enough to keep the franchise going, eventually setting up a pattern where they'd more or less alternate between UC and non-UC productions (the former to pay tribute to the series that started it all, the latter to try out new ideas and keep things fresh without being tied down to the UC story).