Yea developer support seems to be one of the biggest hurdle they are facing. Even FSR is having trouble getting traction despite it being open source and relatively easy to implement. There are more games that have FSR 2.0 modded in than official developer support to date and since FSR 2.0 requires developer tweaking to get it right, modding in FSR into the game doesn't mean it will give you the best image quality/performance that FSR has to offer.
Meanwhile DLSS is officially in 200 games with more to come:
RTX users keep winning this gen. Hopefully Radeon can catch up in crucial areas they missed with RDNA 2 such as with Ray Tracing and Ai Upscaling. They also need an alternative to Nvidia Reflex cause once you understand how Reflex allows a lower input latency even against GPUs with a higher framerate and Reflex disabled, you will realize how crazy it really is.
PC Specs: CPU: 5950X || GPU: Strix 4090 || RAM: 32GB DDR4 3600 || Main SSD: WD 2TB SN850