To expand on your comment:

It's only as good as the total loss and delay for any given route. One weak connection does not define the speed and delay, instead, the accumulative weakness of all used mesh units, from the modem to your computer, does.

Therefore, you usually want to minimize the number of mesh units the connection has to go through, like making a cabled star or mesh topology instead of a wireless linear topology.

Might not be relevant for op, but playing games or using VNC or other time sensitive tasks can become really tough.

This is how I have my house setup. I have four “mesh” routers (google wifi) but each one is plugged into Ethernet for higher throughput (my top floor gets the full capacity of my internet connection now whereas it was like 2mbps using purely wifi).