You have to consider the system as a whole, with today's digital equipment there are delays, latency, propagation delay caused by both ADDA conversion and the finite time that the signal passes through the digital stages, each gate that the signal passes through causes a delay by any other name as transistors, the basic building blocks, cannot switch instantly. These delays happen in digital pedals, mixers, digital wireless systems for instruments and IEMs. The amount of latency that you can hear varies between people, and some chain to be able to hear 2mS. The is ballcocks, it is equivalent to one cycle at 5Hz.
So latency adds any one component does not usually add an excessive amount. Analogue, as @Phil Starr says, has a compander, really a compressor, at the input and an expander at the output. This compresses the signal as it goes in to enable more channels to be used, and expends it as exactly as it can at the other end to rebuild the original system. Most analogue systems use UHF bands and frequency modulation FM.
In most cases, the better the design, the better the end result. There are really two rules of thumb before you buy anything wireless. Do not buy anything on the UHF 863-865MHz band, and do not buy anything in the 2.4GHz band.
Finally, do not listen to Scott Uhl on YouTube. The rules in the USA are very different, and most of the UHF systems he recommends are illegal in the UK.