There are many excellent posts here describing the various characteristics of an aircraft’s service ceiling, One thing not often mentioned in service ceiling discussions is that the service ceiling is determined by highly trained and qualified test pilots using equipment and engines fresh from the aircraft manufacturer. Sort of like EPA Gas Milage stickers on new cars.
There isn’t any good reason to attempt to fly to an aircraft’s service ceiling unless one is a test pilot. There is a design issue with MSFS ATC allowing ATC to issue a climb instruction to an altitude above the service ceiling of an aircraft. The best way to avoid this issue is to enter an accurate and valid altitude in the World Map flight planner nav log. The same recommendation applies to SIDs and STARs. These often contain altitude and speed requirements only obtained by airline jets. It is up to each pilot to verify their aircraft is capable to fly a SID or STAR.