I understand your frustration, my friend.
Honestly, I think the problem with 3rd party development is that we, the consumer, put too high an emphasis on “high resolution” PBR textures. Forum pundants and YouTube infuencers fawn over high resolution textures and besmirch developers that don’t deliver expected eye candy. Accordingly, third party developers provide products with 4K or 8K (yikes!) textures to satisfy demand.
To what end? Sadly, poor performance.
MSFS’s default content, e.g. aircraft, airports, POIs, etc., are created with 2K textures. No one complains about the quality of default planes and scenery. I figure 2K textures are probably good enough as-is, but unfortunately most third party products contain higher resoltution textures to satisfy marketing needs. It is my belief that this lack of consistency in texture resolution between default and third party add-ons is what creates scenarios that harm performance.
These high resolution textures are what, I believe, are killing performance through VRAM exhaustion.