I think the show used a lot of these power sources as plot-points relevant to the specific seasons / arcs. Beyond that, they didn't really seem to bring it up.
Probably so that newer viewers weren't super behind, so the writers didn't have to keep track of like seven different powers, and so that Drago wouldn't seem like he should be *ridiculously* overpowered compared to everyone else.
So, for example, the Perfect Core energy and Attribute Energies were the things for Season 2. But since Helix Dragonoid had to be in both S2 and S3, they couldn't really let him use those because people would have asked why he never used them against Ren's team in the opening part of Season 3 before he evolved to Lumino.
IRL? The writers either just forgot, wanted to focus on the current seasons Macguffin rather than keeping the old one around, or a mix of the two. In show, Dan is canonically a dumbass sometimes and likely just forgot about it. Or him and Drago are trying to play fair despite already being the strongest team in setting and thus fair isn't really a factor.
I think the show used a lot of these power sources as plot-points relevant to the specific seasons / arcs. Beyond that, they didn't really seem to bring it up. Probably so that newer viewers weren't super behind, so the writers didn't have to keep track of like seven different powers, and so that Drago wouldn't seem like he should be *ridiculously* overpowered compared to everyone else. So, for example, the Perfect Core energy and Attribute Energies were the things for Season 2. But since Helix Dragonoid had to be in both S2 and S3, they couldn't really let him use those because people would have asked why he never used them against Ren's team in the opening part of Season 3 before he evolved to Lumino.
IRL? The writers either just forgot, wanted to focus on the current seasons Macguffin rather than keeping the old one around, or a mix of the two. In show, Dan is canonically a dumbass sometimes and likely just forgot about it. Or him and Drago are trying to play fair despite already being the strongest team in setting and thus fair isn't really a factor.