Wait, wasn’t there some furry race they were replacing the Aasimar with?
Aardlings they're called. I don't know much about them and I can't find too much information but I don't think they're replacing Aasimar. Some people asked the same question about a year or two ago and I've yet to see people talk much about Aardlings compared to Aasimar, there's not even a wiki page for them. Then again I tend to stay away from large public spaces discussion tabletop since most of those places fucking suck. Are there any good forums for straight up Tabletop rather than CRPGs and whatnot? I have RPGCodex and RPGHQ for that.
It seems as though they decided not to include them in the PHB after all, presumably because aasimar already filled the niche of "descendant of good-aligned beings" so there really wasn't much point to replacing a perfectly workable race that players are generally attached to. They only appeared in the first and third playtest rules and were never mentioned again, though it seems that they didn't bring up races again in any followup playtests, so I guess they made that call themselves sometime later and didn't feel the need to bring up the point again.
I decided to look up the different races to compare them. Although I haven't seen the new PHB to confirm, RPGBOT's article said that aasimar in the new PHB are basically the same as the MPMM version, but they can choose their transformation ability every time they use it instead of being locked into it. The original ardlings had bonus action flight up to your movement speed (prof. bonus/day), a cantrip and two leveled spells (once/day unless you use spell slots), and radiant damage resistance. The revised ardlings before they gave up the concept had a feature related to animal ancestry (climb speed+unarmed strike damage, safe fall+advantage on jump checks, increased movement on dash (prof. bonus*10 feet), or hold your breath for an hour+swim speed+cold resistance), any divine cantrip that can be changed on a long rest, and perception proficiency.
Compared to everything aasimar get (necrotic
and radiant resistance, darkvision, a free heal once per day, light cantrip, and three transformations to suit different needs but only one use of any per day), I don't think ardlings would have been anyone's first choice to use, especially since all old races are still usable in the new rules anyway. Thus, why go to the trouble of making up something new and lame when something else better already existed they could use? I know making things lame is kind of WotC's deal these days, but laziness is far more of a motivator.
