This is pretty much how I see things. There's no precedent for GW deleting factions since AoS launched aside from the initial purge of the Brets/TK. Furthermore, I see no indication of them wanting to remove more factions in tbe near future. Espeicially with older factions receiving allegiance abilities, artifacts & command traits via the GHBs...
No Darkling Covens, Scourge Privateers or Ordo Serpentis models have been removed from Matched Play as a result of the old WHFB Dark Elves going "Legends". Furthermore, those factions were all included as allies for DoK and IK - another indication they are unlikely to be retired in the near future.
Finally, we seen a number of old factions be rehashed into AoS factions complete with battletomes and a handful of new kits: BCR, FEC, DoK, Bonesplitterz, Maggotkin, DoT, etc. I also don't see any indication that GW will stop doing this any time soon.
All in all, I don't see any reason to stop collecting an army you love right now and feel like this is a bit of the proverbial storm in a teacup.