Pretty sure you guys were effected by the reromanticized effect, that broadly speaking started around the 1850s or so in England though wasn't fully finalized until about the 1970s or so. Solder was just one of the more unified examples of a word being effected due to it being rarely used outside of blacksmiths up until the industrial revolution and it being a relatively easy thing to assume the l was pronounced by the developing metal working tradesmen unless the region had the soder or sodder spellings instead of with the traditional spelling.

How is that ethnocentric? I'm a Californian Redneck barely a culture and sure as shit not a ethnicity. My point was to moreso directly shit on the English in particular who reintroduced the l pronunciation and indirectly caused a bunch of random fuckers to get pissy with me. In hindsight I probably should specified, regardless I am unfamiliar with any dialect pre 1900s who pronounced the l in solder.