Let's just say that with current tyre construction, the manufacturer will recommend a range of rim widths that will get the best out a certain tyre size. Based on that, an "approved" tyre shop will often refuse to fit wide tyres to narrow rims. Matching the rim width to the tire will enable the tread to keep in contact with the road. Pictures of "old" cars screeching round pylons will show them trying to use the side walls for grip, not a good idea.
For a given tyre size the rim width range might for example be 5 1/2" - 7". The narrow end of the range would give you comfort but the wide end would give you much sharper handling. You choose..........