Pokemon should only get access to a maximum of 3 type moves. Their own type, secondary type and a 'pseudo-type'. For legendaries it would be 4 or 5.
It makes 0 sense why Gholdengo can use dazzling gleam, focus blast, psychic, thunderbolt, nasty plot and power gem.
That's
>fairy move
>fighting move
>psychic move
>electric move
>dark move
>rock move
>on top of steel and ghost type moves
All in one pokemon. Now Gholdengo is not the odd example. Plenty of pokemon have coverage for what is their counter. Every fighting pokemon has knock off and u-turn which is super effective against psychic. It's not stats that are powercrept. It is mainly moves being far too distributed and easy to use. Normal moves are okay to spread around because they are not super effective against anything.