Try it, as you point out the newer chips "should" be more power efficient (and they are to an extent) which means even light mode may feel no different to standard, even in general UI usage. The double edged sword here is, even though they are more power efficient, the overall gains is really determined by the SoC Qualcomm geared it towards, in this case the SD 8 Elite is a far more performance chip than an efficiency design, hence it's great gaming and CPU benchmark numbers. To put it in perspective, the CPU can run at speeds over 40% higher than last generations design and none of it's core clusters are efficiency cores, the lowest clocked cores are 3.53GHz Vs the 3.2GHz max clock in the 8 Gen 3. For reference, the 8 Gen3 used 2 efficiency cores which ran at 2.3GHz.
Technicalities aside, the new chips are basically powerhouses, designed on a more efficient manufacturing process, but nonetheless powerhouses designed for heavy lifting. Efficiency wasn't the highest priority for Qualcomm with this generation.