Within reason it's fine. Rim makers estimate the tire width and pressure their clients are likely to use, using the same "recommended tire width" guidelines consumers use. They also monitor what tire companies are rating their tires for, and engineer accordingly allowing for some error on the high side.

Also consider that the side of the rim wears thinner from brake wear over time, so the engineering limit is based on the worn thickness, allowing even more error on new rims.

Except at extremes, hoop stress the tire applies to the rim shouldn't be a worry, but it is something to keep in mind if you like wide tires and high pressures.