JH7110 (VisionFive2/Star64): adopts TSMC’s mature 28nm process technology.
BCM2711 (Raspberry Pi 4): 28 nm process
There is a reason why 28 nm process nodes are used in price optimised SoC’s, because it currently offers the maximum number of transistors for the minimum price. Lager transistors can use older nodes, which would cost less, but end up using a much larger area of silicon which costs more. And smaller transistors need more expensive newer nodes (which are in high demand) which costs more to use, but also use a smaller area of silicon. Both cost more per transistor, 28 nm process will be the optimal in terms of what you get for what you pay for at least the next 4 years, maybe longer.