American pilots are not shy to use "unable" when asked a task by ATC. But Asian pilots may not be so confident in their environment. Taipei ATC would take a dim view of pilots dis-obeying ATC "commands". It is a potentially career ending move for Taiwanese pilots.
TAiwan air traffic is dense and it's important everyone follows their instructions.
Perhaps this caused them to not query why they are flying into mountains when they are supposed to be headed towards the ocean pronto.
Unconfirmed rumour has it the pilots have been suspended pending review. And no rumour here, the Taiwan CAA is looking into this incident closely.
Pilots facing dismissal and loss of license.
p.s. TAiwan is only 90 miles away and only 45 miles away from no fly zone of "enemy" China and there are constant military sorties around the island. ATC talks to Taiwan military in Mandarin (not English). Therefore even more important civilian flights follow their instructions to avoid conflict. Especially civilian flights commanded by pilots unable to understand Mandarin.