HO train enthusiasts?

I used to be into HO stuff many years ago. But, with some exceptions, it's not very valuable. Especially the older locomotives because when they sit for a long long time they need to be taken apart and gone through. The model railroading hobby has really fallen apart. There used to be train shows etc., and now people would rather play video games and throw their lives away on Twitter/Facebook/Instagram/Tik Tok/YouTube

I think it really depends on the brands. I can't think of any good catalogs. It's not like stamp collecting. Ebay is usually overpriced.
Here's a link with a general outline Charles Cooper's Railway Pages - Disposing of model railway and other train stuff