It is hard to make a bad EL84 amp.
An SE EL84 in triode outputs 1.5-2 w, an SE 2A3 closer to 3.5w.
An EL84 amp wil also be much less expensive. I’d guess even a good EL84 PP would cost less than a good 2A3 SE amp. I would expect cost to be why you suggest people ar egetting EL84 SE instead of 2A3 SE.
I am currently listenind to my mighty (3.2 w at clipping) PP EL84 triode amp and boy does it sound good (FHXL with MA CHN-110).
We did build a string of ever better SE EL84 amps, starting out with a Decware clone. We ende dup with a scade feedback arrangment which we liked better and it outout 4.9w at clipping.