BBC news says Kabul airport is calm, is this because the Taliban's checkpoint outside the airport are stopping people from going in and their street

Yes, I'm sure that's it.
The Taliban is simply misunderstood scamps.
Yesterday, BBC reported that the Taliban was chanting "Death to America", but in a very nice way.
So, it's not always WHAT you say, but how you say it.

Sounds like they are doing a good job.

No, people are back in the streets and the street markets and stores are open for business. Sadly, it most likely won't last after the USA pulls out its troops at the end of the month.