In this case, Dr Lemire is using software he co-wrote to test the performance of the M1. It makes sense that he'd be focussing on that software (Simdjson) which wrings as mich speed out of the processor as possible by using vector instructions and avoiding branches. His coauthors blog iirc is even called https://branchfree.org, to indicate the importance of avoiding branch mispredictions to keep the cpu foing quickly.