[Dormant] moved to !historyphotos@piefed.social

That does seem pretty feasible. In fact, the first thing I did before responding was check when color photography became popular; at a glance there wasn't an answer about commonality in the wiki page, but color photos were apparently invented most of a century beforehand, so really I'm not sure either way.

I hope this entirely unproductive comment helps. For the time being, I'm just going to assume it's real and that this guy took pride in his trade.