Scotch gambit or Scotch game?
Is the Scotch good?

Gary Kasparov played the Scotch Game twice against Anatoly Karpov in their 1990 World Championship match.....Kasparov won this game (the other was a draw)...
https://www.youtube.com/watch?v=5QLgVdlgJqA
https://www.chessgames.com/perl/chessgame?gid=1067288
How to play Scotch Game...
https://www.chess.com/lessons/learn-to-play-the-scotch-game

It's a good opening.
And at lower levels you're probably seeing a lot of this
And now Bc4 Bf4 Nc3 0-0-0 is really nice. I've done a lot of this with colors revered when white misplays a scandinavian.
Moves like Nc3 and Bc4 hold on to d5, so black usually plays d6.
Bf4 targets d6 because black usually gets restless with the queen in the middle and plays c5, and now your Bf4 helps you win the d6 pawn.
I'm not saying this is how strong players play black, I'm just saying you'll probably win a lot of games this way

If black remembers all that (or finds it OTB), he's completely winning otherwise... heh.

Scotch gambit or Scotch game?
Game
The Scotch Game is a legitimate alternative to the Ruy Lopez. It is far superior to the Scotch Gambit, a typical opening played by amateur, youth players. Against correct defense, White gets zilch out of the Scotch Gambit.
But the Scotch Game (1.e4 e5 2.Nf3 Nc6 3.d4 exd4 4.Nxd4!), it's a whole different story. The only reason it is not played "as often" at the GM level is that the position is more open than the Ruy Lopez or Italian Game, and at the GM level, more open equates to more drawish. That's why the Petroff is also a draw weapon at the GM level, along with the Berlin. But if you look at games below the GM level, many Petroffs, Scotches, and Berlins lead to decisive results.
But from a soundness and legitimacy perspective, the Scotch Game is perfectly sound, and White can get a small advantage, unlike the Scotch Gambit. Now how White follows up matters. For example, after 4...Nf6, Kasparov's 5.Nxc6 is stronger than the Scotch Four Knights (5.Nc3). The latter, like the Scotch Gambit, is nothing better than equal, but after 5.Nxc6 bxc6 6.e5 Qe7 7.Qe2, a very complex game arises that can lead to three results! If I had to take a side in that position, I'd rather have White with the space advantage and better pawn structure, but Black is not busted by any means either.
I've been playing Scotch for about a week and seen my win rates sky rocket, but people told me to not play the Scotch.