Yes exactly, because of the situation in Ukraine and the inherent complexity of these machines, it is much much easier to keep a Type 69 running than a T80UD, we can produce spares for these (and we have enough spares to fix the things we cannot produce), but it’s not worth using them on these oldest UDs. Keep in mind that there’s many shared parts between the UD abs AK powertrains, so not wasting them makes sense, Also Keep in mind the first 35 UDs delivered to PA were quite inferior to the later 285, so PA might have decided it was not worth using spares and stuff on the older ones, especially once their hulls reached an unusable state (keep in mind the rest of the UDs were rebuilt and upgraded instead)
These had older Cast turrets and hence weaker armor and generally the quality of these early few tanks was not up to par with the later ones. I guess that played a part in this decision, though it could have been just this one specific Machine getting into an accident and being retired, but I assume it was the entire first batch because I haven’t seen those in any photos or videos for years now, unless they were upgraded to the later standards in the programme and we didn’t see it.