the very short answer is related to balance of trade + geopolitics. It's not at all surprising if you know how textiles are like, to understand why the first tools that was mechanized and ushered in the Industrial Age were related to this industry (Europe had domestic and colonial reasons for wanting to speed this up as well as break the domination of India).

so yeah, thread made better sense for us to source rather than do (Indians had the best fine cottons, and until Egypt and America were British-colonized, nowhere else can compete; Nusantara don't have the best soil for cotton as a mass industry; China had the best silk and pretty much made it illegal to export the silkworms out), and we had other things that make better sense to trade like local organic goods; our marine navigation etc. Weaving tech for the nusantara groups (the Straits Chinese and later waves had a different cultural source) came from the north via Vietnam. Weaving basically became a thing in every cultural group worldwide, because textiles are expensive - in our case, we're so rich from the other things to get that we actually did more trade with finished Indic textiles, but eventually we did it too because you can't just wait for India (not China as textile source though; we're an Indic sphere region) - lol this is why the British also developed a weaving industry in Manchester and northern England.

In Malay the name of the loom (kek siam = siamese loom), tells you where our tech initially came from. This was the same with the more Malay/Muslim groupings in Borneo as well (the transfer of tech, which is via trade), while groups like Iban maintained backstrap weaving (where the loom tech requires your body to be part of the frame and tensioning; unlike the more stationery cultural groups who put in more energy in floor looms etc that're non-moveable).

alamak, still long answer hahahahaha