btcd has been around since 2013. I stopped using it because the performance wasn't all that good (i had btcd and bitcoind both running on different machines, i switched to one node running bitcoind afterwards)... Which was fine in 2014/2015 (which was around the time i used it iirc), but around ~2017(ish) the amount of broadcasted transactions rose untill the point most of the blocks were filled to the brim. The sheer size of the blockchain at that point in time, combined with full blocks made it obvious to me that i had to move away.

The reason for my move from btcd+bitcoind (two different nodes) to 1 node running bitcoind was 100% performance related, and had nothing to do with the consesus algo. AFAIK, btcd is updated frequently and is a perfectly valid (albeit, less performant) full node that can be used as a mining node. I'm not sure if anybody is doing this tough, and my experience with the project stopped many years ago, so i cannot comment on recent topics.