Google Wifi Mesh...no real benefits?

I don't see any noticeable difference at all.

My home is 1400 sq feet. Internet comes into house downstairs and first google wifi is my primary wifi. I got a second one today and connected it upstairs. Home is very old construction, very thick walls and floors, etc.

After configuring the second one, I didn't notice any difference. Speed test is the same, youtube vids load the same, etc The only difference I can see is my chromebook now says 'strong' instead of 'medium' in the general vicinity of the new 2nd access point.

I am thinking of returning it as it doesn't really seem to provide any benefit? Am I not understanding the use or benefits of this thing?