No, M1 is clearly slower in multi-core (to be fair, it has fewer threads). Not sure where you got your numbers from. 5900HX gets about 7800 in Geekbench 5, and the difference is much larger in some other multi-core tests. For example Cinebench gives 7800 for M1, 13800 for 5900HX.
It says in your link there is a 3% difference in "Geekbench 5 (Multi-Core)" between the two? I would say that is practically equivalent, particularly since 5900HX comes in several TDPs. (It says "54 Watt" at your link.)
I took my data from perusing the Geekbench DB for the latest submissions...
Yeah I agree GB5 is roughly equivalent, others not so. Anyway this is just me being pedantic as so many people seem to think for whatever reason that M1 is the most powerful mobile chip while it certainly isn't. I do expect Apple's follow-up chips to take the multi-core lead too eventually.
An M1 is about 1700/7600.
So call that a tie for MT, and 20% faster in ST...with a chip using about a third the power.