While DL is not the worst on SEA - ICN, Delta offers the worst product on SEA - TPE, comparing to the competing Taiwan carriers

And last time I was in Taipei, DL doesn't even have a gate, it's a remote spot.

And of course, lack of connection options to Southeast Asia, unless DL strengthen the partnership with CI.

Taiwan itself does not have that demand to fly point-to-point between Taipei and Seattle, and the demand between Taiwan and U.S. has been diluted by UA TPE - SFO, massive Cathay Pacific operations in TPE, and 3 Taiwan carriers BR, CI, JX