I realize your points, but Vietnam, at the end of the day is nothing more than a convenient proxy for China - for exports to the US and EU.
Backward integration in textiles in Vietnam is minimal (spinning/weaving) even compared to Bangladesh. Vietnam does not grow any cotton either AFAIK. So - they are dependent in large part to China for all textile inputs including woven/knit textiles sometimes, if not yarn and fibre. This is just to circumvent US sourcing tariffs for Chinese textile imports.
To those who wish to have Bangladesh build space shuttles, we need to build infra first (roads, bridges, highways, ports). Have to learn to crawl first, then walk, then run.
Everything is produced in a third world country because people somewhere else wants to buy it cheap. If you don't have a large local market (for say, automobiles) - which we don't, then we have to find buyers overseas. If we don't, then I guess we won't make/export them.
Nothing is made to satisfy nationalistic ego. They are made in factories because there are buyers overseas who want to buy them (if they are cheaper to buy and better quality than other options - like the RMG you guys diss so much).
RMG is what Bangladesh will keep making, until production shifts to say pots/pans and hand/power tools. Last time I checked, those are still better made in China for export. Even other Asian countries cannot compete. So - there you go.
Eventually we will start exporting pots/pans/pressure cookers as well as hammers and wrenches (in massive numbers, to be profitable). But the demand for those are not as intense as shorts and T-shirts. You all need to be patient.