I haven't regretted moving over to the R5 and RF glass. However good luck now you have sold your EF glass, ordering and buying RF glass. I ordered the RF 100-500MM Lens on 17/08/21 and am still waiting. Apparently, I am number 16 on the list and they are not receiving any stock so unlikely to be before xmas. Not sure which xmas, 2021 or maybe 2022. I don't think it's just Canon suffering with the worldwide chip shortage so I'll just have to be patient. Hope you have better luck.I love it.
When I decided to go to RF (first couple R reviews were just available) I sold a dozen-plus EF lenses, keeping only the 135/2, 180/3.5 and 600/4IS.