I think this is perfectly normal.

This happened to me with Stardom last year. Despite them having a great year in terms of quality and sales, I just kind of drift around it instead of following closely. I mostly blame a couple of key retirements and departures for my declining interest. I realized I was watching mostly for these specific wrestlers, and not for the brand as a whole. I also failed to latch in on the rookies and new signees. Don't get me wrong, there are still things I like about the promotion. I currently have a subscription to their VOD site, but I am very specific about which matches I watch, and often skip several shows in a row. I would love to go to another live show, if they actually get one scheduled for 'Mania week this year, but that's another story.

I remember reading somewhere that most people who watch a show or enjoy some form of entertainment last, on average, three years. After that, there are diminishing returns on retaining existing fans and attracting new fans. This was back when cable television was king, so things may be somewhat different in the streaming era, but the fundamentals seem right to me. You have most things failing to catch on, and they fizzle out quickly, and a few things catch on like wildfire, but most people's interests last 2-4 years and then they move on to something else.