[GMB] Multiple Cities in Service Area?

I tried researching this topic and some people insist on only placing one city per GMB as your service area. Others say it doesn't make any difference at all.
After reviewing my competitors in a bit more detail, I noticed one of them was ranking (poorly) across multiple cities after setting the entire country as his service area.

Does anyone have experience or tips on how they like to go around ranking your money GMB acrossa further radius?

My personal listing is right at the edge of the city border, so even though my GMB only lists my own city as my service area, my rankings seep into that other city as well.
So, seems like it isn't necessarily holding me back from pushing outwards radius-wise, but it definitely isn't helping.

If you’re talking about the service area setting inside of GMB, then that is meaningless. That only serves to show your customers what your service area is, it will list it and also show it highlighted in red on the map.

But when it comes to how Google ranks you, what you select as your service area doesn’t matter.

If you want to rank for more cities around the one that you’re based out of, making city-based landing pages works very well.