Cuckchan thread is shit and this should've just been in the souls thread, so sageposting, but I will contribute.
I think the biggest problem with solo invasions and why they don't feel as fun in ER and DS3 compared to past games is the rise in popularity of net-decking when it comes to builds and all that. Following clickbait youtubers or looking up "most efficient PVP invasion build" and just following that. Ends up making things very stale in the long run since all the invaders end up feeling the same or just rushing to the most OP bullshit and not experimenting. That practice makes PVE discussions more boring too and leads to people skipping a layer of engagement when it comes to buildcrafting in these kinds of games, such as in Remnant 2 where 90% of people you'd encounter would be running one of the same few clearly-guide-made builds, but this shit hurts the PVP side the most by removing a lot of variety and thus the invaders get stale fast. Look at the launch of DS:Remastered compared to the launch of the original when it comes to invaders and the experience from such and the difference was massive.
Like, I've been doing an ER run with taunter's tongue on and 95% of the invaders were using the bloodhound's fang and the same min-maxxed armor set in the earlygame. It's just fucking tiresome. I was so happy when I finally fought a guy using a poison sword and board even if it was a deadlier build (since no poison cures that early unless you route for them) it was a much more fun fight. Or when I ran into a bleedmaxer using an uchi and a nagakiba once I got past Godrick. I remember back in DS2 where nearly every invader would be on some wacky bullshit and there was a lot of build and fashion variety, but now everyone has a stick up their ass about meta, twinking, netdecking, and minnmaxing. DS3 was bad about that shit too, and I despised it, but at least you'd occasionally see some cool shit.