Pilot reported taking evasive action to avoid a mid air collision with another aircraft. The Pilot reported very heavy air traffic and was directed by ATC to restart the arrival.

Narrative

Flying Aircraft X; a Beech Bonanza A36; on the ZZZZZ arrival to ZZZ; at ZZZZZ; was instructed to turn right to 090 for left base to Runway XX ZZZ. A few seconds later was told to turn right and restart the ZZZZZ arrival due to congestion at ZZZ. After rolling out on a heading of 180; Aircraft Y passed overhead of Aircraft X; filling the windscreen. Conjecture. Aircraft Y was identified with ADS-B data from the ADS-B replay website. Based on that ADS-B replay; and recordings from LiveATC; I assume that both planes responded to the command to abort and turn south to return. Also; based on the position of the planes; I don't think either pilot could see the other (Aircraft X would be below; ahead; and to the right of Aircraft Y where it would be behind the cowling; Aircraft Y would be behind and to the left of Aircraft X where it would be blocked by the left wing during a right turn. Further conjecture. Both airplanes were following Vans RV's and likely both responded to the initial command at ZZZZZ to turn right to 90 degrees to follow the east road to XX. This put both planes on parallel paths making the turn to the south very problematic. Both planes are low wing; and the command to abort/return to the start at ZZZ1 was directed to 'low wing just turned east' (paraphrased) which is pretty generic and applied to both aircraft. ZZZ is very busy and congested - such density along the arrival can lead to this kind of near miss. My conclusion is that I will not fly the ZZZZZ VFR approach again when the congestion is so high. Having a passenger to act as spotter would also help (I was solo).