Even the basic Lachenals of the 19th century had the sort of reed-and-frame arrangement set into reed-pan that tended to be a bit delicate. Whereas button accordions of the same vintage had what have come to be called "accordion reeds" stuck on top of reed-blocks. The latter is inherently less sensitive to environmental vagaries. Now, cheap concertinas from the last few decades (and even some better ones) have reeds waxed onto blocks like accordions. I don't recall seeing a 19th-century concertina with such an arrangement.