I always assumed My Little Ponies Tales was G2 but apparently not. It wasn't widely known to many people, only consisting of one video game and a few toy lines. From what I can discover, it had a PC game called 'Friendship Gardens' where you design and care for your very own My Little Pony, teaching her to jump and to gain enough courage to eventually cross the rainbow. Though, this is based off research since I didn't have the game as a child.
The toys were kind of unique with having gems for eyes:
I remember this vividly as I had one of these as a child and thought they were so cool. Granted, I got one of these well after 1997 since I wasn't born until 2003 (G3 began around then and ended in 2009).
But coming back to the reason why G2 isn't talked as often as the other gens (G1, G3, G3.5 (yes, there's a reason why), G4 and G5) is explained quite nicely above by Fhaolan. With G2, I think around that time they were focusing on the toy line. Also, because while Europe loved it, it was... kind of a flop in the US. It only lasted a year from 1997 and despite the toys and video game, it had no TV show/animated show. So, it gets skipped by the majority of MLP fans, especially those whose first introduction to MLP was G4. But to those who first got introduced to MLP by G1 or G3, they have a slight idea on G2.
EDIT: It's 1997, not 1977. My bad!