After doing some research on YouTube here is what I think is happening with R7 AF.
The R7 sensor is a high density 32.5mp. The sensor also controls the AF. The sensor response time is not part of the specs that Canon releases. The Canon Community has measured the sensor and found it to be a bit slow at 31ms. That’s half as fast as the R6II sensor while the R7’s sensor has even more pixels. The communication between the lens’ AF and the sensor is too slow at times so that the sensor can’t control the AF fast enough. The result is that the AF is off the point every so often. This issue becomes more pronounced at high drive rates especially H+, 30FPS with Electronic Shutter. Over cast, darker, low contrast situations accentuate the AF problem.
I haven’t used my R7 at H+, 30FPS, ES very often so I haven’t experienced the AF problem. Also, I tend to shoot birds only on sunny days with the shutter set at Elec. 1st Curtain @ 8 FPS. Therefore I have no complaints after 2 months of shooting with my R7.