I don't see what the big problem with them not referring to the Doctor's memory loss so much, I mean TOS had Uhura's memories get wiped by Nomad and she's fine by next episode.
Two points. First, you're comparing a series made in the mid-sixties with one made in the mid-to-late nineties, which isn't fair or particularly useful. Second, I don't think many fans would refer to the way that 'The Changeling' completely glosses over the fact that Uhura has lost all her memories as a virtue of the episode.
TOS was wholly episodic, whereas Voyager had a certain degree of serialization and need for continuity inherent in its very premise and that was belied by the producers and network's deciding that they wanted it to be able to be broadcast in an episodic fashion for syndication.
I wouldn't argue too strongly against your assertion that Star Trek
is "wholly episodic," but I do think it had some of the same occurrences of what might be described as "minor continuity" that you are using to praise Star Trek: Voyager
-- In "By Any Other Name," for example, Kirk both mentions that the Enterprise
has already visited the Galactic Barrier (a reference to the events of "Where No Man Has Gone Before") and asks Spock to use the same trick he used to fool the guards on Eminiar VII (a reference to the events of "A Taste of Armageddon").
-- In "Turnabout Intruder," Kirk directly mentions the events of both "The Tholian Web" and "The Empath." General Order Four from "The Menagerie" is also referenced (although the script gets the number wrong).
It has been suggested that TOS could be viewed in any order. Like VOY, that's not *quite* true, because of minor continuity, but the fact that both series were broadcast out of order without any viewer difficulty demonstrates their episodic nature.