The contracted speed does not fix everything
Many homes pay for 600 Mbps or 1000 Mbps and still suffer dropouts, rooms without signal or unstable video calls. The reason is simple: the speed reaches the router, but then it must be distributed properly around the home.
What really makes the difference
A good router location, well-placed WiFi points, cabling where it matters and proper device separation can improve the experience more than paying for more speed.
When more speed is worthwhile
It makes sense with many users, intensive remote work, cloud backups, simultaneous 4K streaming or heavy downloads. For normal use, a well-configured network is usually more important than the number on the contract.