But Malaysia has a far smaller population than the other 3…

https://www.channelnewsasia.com/news/commentary/coronavirus-covid-19-air-travel-asia-market-changi-airport-sia-12680268

In Southeast Asia, Malaysia, Philippines, Thailand and Vietnam also have sizeable domestic markets with at least 25 million annual passengers.

Southeast Asia’s top four airports – Bangkok Suvarnabhumi, Jakarta Soekarno-Hatta, Kuala Lumpur International and Singapore Changi – are similarly sized, each handling between 60 and 70 million annual passengers before this crisis.

Changi is by far the largest in terms of international traffic as it is 100 per cent international compared to 81 per cent for Suvarnabhumi, 72 per cent for Kuala Lumpur and only 23 per cent for Jakarta.

1 month to re-activate the planes

https://news.ycombinator.com/item?id=23011707

Well, there’s some nuances.

If they’re mothballed (skin covered and various systems pickled), then about a month of work each.

If they’re not mothballed and they do weekly or bi-weekly maintenance on each plane like they’re supposed to, then an inspection, and then they’re ready.

So the worst case is a month, and the best case is an inspection plus 30 minutes.

Also, note that in the mdoern era, a lot of avionics require periodic updates, which also have to be performed before flight.

But if I was the FAA, I’d be requiring crew-only acceptance flights before any revenue flights. You never know where those pesky wasps built a nest, or if those AOC sensors corroded, etc.

Source: commercially-rated airplane pilot.