All airlines, including locos now overbook. They almost always get it right and when they don’t they find volunteers and/or pay compensation.
That seems to be working for them.
If you can’t get a seat on a flight you should know that the capacity, plus their overbooking profile, is gone.
Why reinvent the wheel.
Not saying their procedures for oversales can’t be tweeked, they should be. But we only hear about when things go pear-shaped.