imo carb isn't clean
fully disassemble and soak metal parts for a week in carb dip rotating body at least once a day to purge trapped air..
30 minutes or less in ultrasonic cleaner is another method though it may take more than one session..
After watching video several times I'd guess the vacuum piston isn't rising as it should thus the main jet in conjunction with needle jet aren't able to enrichen the fuel mixture. Piston should move freely up and down without any binding.
inspect rubber diaphragm for splits. assure diaphragm is properly seated when attaching top cover.
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I would expect somewhat better operation when you slowly open the throttle which leads me to speculate idle circuit isn't clean.
Pilot/AF screw primarily influences idle circuit while your video indicates throttle often opening at least 1/2 way to full throttle position where AF screw has little influence.
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I have no cure for clogged accelerator nozzle other than soaking which may not dissolve the blockage.
What are the cylinder compression readings?
Carb cant work properly if pistons don't suck as they should.
there comes a time to grab at straws, eliminate all possibilities.