There are considerable safety concerns regarding private jets, mostly down to the quality of the pilots. At the bigger airlines, pilots are unionized and have consistent schedules they work and routes and aircraft they fly. It’s reliable work and where most pilots (even military) end up.

Meanwhile private aviation needs to be flexible and easy to set up. Contrary to your comment this is the sector that you can usually expect to find more unscrupulous operations and pilots who are basically just Some Guy. Most of the near miss accidents lately have involved private planes (though that can often be attributed to problems in the ATC network).

As for the doors that’s more of a Boeing specific problem, they’ve made a lot of questionable business decisions in recent years and this is the fallout of that. Airbus planes don’t seem to have this problem, and customers seem to be making it clear that they would like their planes to work thank you very much.