Mesh is almost all marketing hype. The majority of the so called "new" function is a slightly different form of wifi repeater and not all device even have separate radios for the backhual.
You should never use wifi repeater functions if you expect performance. You are transmitting extra signals all of which can interfere. You automatically increase your latency by having mulitple wifi hops.
Be interesting to see what wifi6 really does. It will well over a year before enough equipment is on the market to really say. You can not trust some of the early installs by the fan boys. It will be when the technology is used by people who can barely take it out of the box and turn it on.
The major issue with wifi is everyone stomping...