Business jets are built to save time for their passengers, who are often quite wealthy. Therefore, the design is based around favoring speed over efficiency.
Commercial airliners are built to make a profit for the airline, while transportingby moving passengers faster than the alternatives (cars, trains, and buses). And and keeping a useful schedule with connections to other flights. Therefore, the design is based around favoring economy; saving money on fuel to maximize profit.
Many airliners can cruise faster, but at the expense of more fuel burned and tickets that are less affordable.
Many business jets can cruise slower and save money, but the important, wealthy passengers often wish to make the trip as fast as practical for their next business meeting (or tee-time).