IMO the problem with modern GPUs is that the amount of stuff that requires dedicated cooling has gone up; In the early days the GPU die generated the lion's share of the heat and as long as you had a bit of airflow the VRAM packages and VRMs were cooled with minimal heatsinks.
These days, all three things require dedicated cooling with serious heat transfer (so heatpipes or heavy duty heatsinks) and the variable nature of where those things are positioned on different models of graphics card mean that designing a cooler that can effectively remove heat from 4-16 VRAM packages and a row of VRMs is damn near impossible.
Every single mid-tier AIB air-cooled card and above has a big old fin stack attached to some heatpipes or vapor-chamber that contacts the GPU die, but then they also have to add additional plates that make contact with the heatpipes or finstack that cover all of the VRAM packages as well as the VRM region(s) of the board. The size, orientation, and mounting locations for these additional plates is bespoke to each and every model made, the one exception being a reference board design - but even that is only applicable to one tier - the RTX2060 reference board is incompatible with the 2080Ti board, for example.
So an aftermarket air cooler that is genuinely equivalent to an AIB air cooler yet compatible with multiple models is going to need some kind of Lego-like assembly of VRAM heatsinks and heatpipes that are adjustable like in those 100% passive cases where loose heatpipes are clamped between blocks and thermal paste to connect CPU/GPU to the case chassis. It's going to be complicated, heavy, ugly, bulky, and expensive to make.
Let's assume you're okay with those downsides, you still don't get a backplate, universally-compatible fan headers on your GPU board, fan control, and (if you want that sort of thing) RGBLED,
So, previous aftermarket solutions worked because with only one item to cool (the GPU die) a single huge heatsink could be moved around so that it lined up with that GPU die and that provided cross-model compatibility. The solutions that do that today rely on tape or permanent epoxy to glue small, inadequate, isolated heatsinks onto the VRAM and VRMs - and we know from plenty of reviews that unless these seperate heatsinks or heatplates are connected to the rest of the fin stack by heatpipes, they overheat and suffer.
Why spend lots of money on a bad solution that won't be adequately cooling your VRAM and VRMs when the AIB's are custom-making solutions that do for much less money? When your AIB model fans die and the card is out of warranty, look at deshrouding the existing heatsink and finding a DIY solution to mount standard 92mm or 120mm fans to it instead - and if yuo can make use of the existing fan control header on the GPU board, even better!
