The only way you’ll really be able to test this is if someone gets a pcie 5.0 system with faster M.2 drives and much better CPU’s.
I’ve just ran another test for the sake of it onto a faster m.2 drive i have, and only got marginally better results. I would imagine that everything from CPU, pcie lanes (usage etc), chipset, M.2 and network gear will impact this test.
If the speedtest shows the expected results, then you’re fine (as that is downloading / uploading data still).
One thing i will do is ask a friend of mine who lives in london and is on 3Gbps internet symetrical to give his steam a test (As he has the same CPU, networking equipment and M.2 as me) and see what he gets. But i reckon the issue here is bottleknecked equipment or steam itself.
Edit:
Found a reddit post here: https://www.reddit.com/r/Steam/comments/10nhtsr/testing_the_limits_of_what_download_speeds_steam/
He managed to max out a 2.2Gbps connection on steam. So it’s nothing to do with steam and more to do with end user hardware.
Last edit, i promise.
M.2 drives have their marketed or advertised speeds. But i’ve NEVER seen a real world test hit these speeds. Even if you run CrystalDiskMark, you won’t get them speeds. So no point really relying on that, i’d pay more attention to cache etc as someone else explained.