You also have a F9000 feed rate in there too. It is applied to some Extruder load/unload as well as that last block of X/Y moves.
As you said, a large quantity of small moves plus the high fees rate together can cause issues.
I recently wrote a config document related to an single hot end / multi extruder setup. Mainly focusing on SuperSlicer setup. I break down the tool change by g-code and settings. It might be beneficial to take a look at it and adjust some other settings.
https://klipper.discourse.group/t/x-in-1-out-non-mixing-extruder-automate-superslicer-filament-swaps