This referenda is for the network to signal that they agree with increasing the recommended core count for reference hardware from 4 to 8, starting with January 2025, the rationale behind this has been already presented and discussed here: https://forum.polkadot.network/t/rfc-increasing-recommended-minimum-core-count-for-reference-hardware/8156 and advertised among validator groups on Polkadot validator lounge and Kusama validator and people seem to be generally on board with it.
Summary
The polkadot binary is a multithreaded program that will benefit from having more hardware cores available, and all configurations are tuned to take into consideration the worst case scenario on the worse recommended hardware configuration. Currently, the minimum hardware requirements recommends at least 4 hardware cores with SMT disabled.
With async backing enabled parachains can now produce bigger blocks which take a lot more time to execute, at a minimum each validator have to check(re-execute) each relay chain block at least 7(relayVrfModuloSamples = 6 + 1 for backing) parachain blocks, given only 50% percent of the CPU cores is allocated for this operation, the average parachains block execution times will not be bigger than 1.7s(2 cores * 6s / 7 checks).
With all that in mind, we think that raising the minimum core count for validators from 4 to 8 is a change that greatly helps the Polkadot network overall to prepare for a future where usage increases 10x or more and it is a change that we should start proactively rather than wait until the maximum theoretical throughput is met.
Note
There will be no change in the way polkadot binary behave when a given machine does not satisfy the reference hardware requirements, it will print a warning and continues executing using the available resources.