This is the only correct answer. Service provider WiFi gateway modems are only ideal for light usage and minimal coverage.
For a modern home WiFi network I dont recommend repurposing old routers as extenders. This likely still leave you wanting.
You are left with one of two choices, wire...
This kind of analysis keeps these companies feet to the fire.
It's thankless work, but some of us here really appreciate those going beyond the benchmark and RMA experience reporting.
Sometimes you just gotta know why and it itches at your brain until you do.
Microsoft would do a lot of people a favor by creating a "Windows for Workstations" SKU that slowed down the micro-release cadence, rolled back the forced updates and gave businesses the Windows 7 experience they desire.