Personally, I wouldn't buy into the RTX stuff today. There is still a lot of work to be done and regardless of how impressive you think RTX is currently, by the time we see a mature use of ray-tracing in games, I suspect the RTX 2000 series will struggle. This is first-generation hardware from NVIDIA and clearly the software ecosystem isn't ready, as we only have one game (Battlefield V) and one student project with it (Q2VKPT). Another game should be launching soon with it (Metro Exodus) but also a game that released months ago still hasn't gotten it (Shadow of the Tomb Raider), despite being shown with it for the Turing launch.
Now, that doesn't mean don't buy an RTX 2000 series GPU, just that I wouldn't consider the RTX support a significant positive for it or a significant negative for any other product. Get whatever fits your need best, and if accelerate ray tracing is important to you, I'd say buy something less expensive and save your money for something in a year to two years, when NVIDIA will have its second or third generation RT cores out and AMD will likely have launched the ray-tracing ecosystem it is working on.
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