The most interesting part about an M1 architecture is an absence of any fan. But, still, from a back-end developer point of view, the one has to wait at least 3-6 months for the software to embrace an M1 chip.
M1 MBP fan comes on pretty quick if you run something like wireguard-vanity-address which will use all 8 cores at full whack. Other than that, it rarely comes on for me.
From benchmarks it only kicks in after like 10 minutes of sustained heavy usage e.g. rendering.