Is the 2...nf6 scandi considered bad?

@nMsALpg seems about right... Maybe I should just stick to e4 e5 because honestly while it can be boring it gives me good results. I'm pretty scared to go for anything new in a serious match.

I know several class A players who use it with good results.  The one problem you will run into is if your opponent knows you and knows you like this defense, you are very easy to prepare for.  The setup for White is very simple and there are not many move order tricks they have to be aware of.  Both sides are likely to get out of the opening nicely, and the fight will be largely who executes their middlegame plans better.  In short, if you want to play it at that level, it is definitely feasible; however, I would also pick up something else to go along with it from time to time (something like the Caro-Kann can be a nice thing to pair with it as you will often end up in similar structures).

"bad" is a bit harsh.  Obviously, he cannot go wrong with the double King's Pawn, but if he is looking for an imbalanced game where he can try to outplay the opponent, I agree the Scandi isn't likely to be that.  In many cases it is just too passive to create such an imbalance.

Personally, I like the Sicilian for that, but I can understand not wanting to wade into the theoretical waters.  Though, it might be worth looking into if you enjoy playing things like the Hedgehog structure, for example.  You may be able to work out your Sicilian lines to get you to that setup from most of White's options.

The Scandinavian as a whole isn't very good.

After 2...Nf6, I find 3.d4 Bg4 4.Be2 and 3.d4 Nxd5 4.c4 to both be better for White.

That said, even after 3.c4, White has better than 3...c6 4.dxc6? Nxc6, White should instead play 4.d4!, leading to the Panov-Botvinnik Attack.

Still, I think 3.d4 is stronger.

Sure, "bad" is relative.

The fun of the opening is when white takes the pawn and tries to keep it... but at a certain level players don't do that anymore... even if they don't know theory they'll "feel" it's wrong and do something safe instead.

As a former Caro Kann player that did not like constantly facing 3 e5 I switched and played a lot of Scandinavian games in all it's forms --- 2...Qxd5 followed by 3...Qd6, 3...Qd8, 3...Qa5, and 2...Nf6. I had my highest hopes on 2...Nf6 but seemed to struggle the most with it. In the Portuguese variation (1 e4 d5 2 ed Nf6 3 d4 Bg4 4 f3) black appears to be under an even darker cloud than ever these days. I finally decided to try to 'upgrade' and recently bought a repertoire book for black on 1 e4 e5. Playing 1...e5 is quite a change for someone used to the Caro/Kann and Scandinavian. 

its just psychological advantage, your opponent gets so confused he misses mates, forks, and others.

I couldn't find anything wrong with simply retaking on d5 with the Queen if White played 3.d4 or 3.Nf3... there was no clear punish. Because of that, I regard 2...Nf6 as the more optimal move order offering a chance for White to fall into some sort of dangerous gambit, with nothing worse than a transposition to Scandi mainlines to fear. Of course it also leaves your options open for 3...Bg4 or 3...Nxd5 if either are interesting to you.

It’s not that bad. It’s not sound enough to be played often at super GM level but I could play it in my tournament games and probably still do okay, certainly vs sub 2000 opposition. 

3. d4 Bg4 is a fun system championed by GM Smerdon, whose video on the topic you can easily find on YT (and who has also written a book about it). He would argue 4. Be2 is = and would admit white’s better in the mainlines but it’s quite complicated. A simpler alternative for white is 3. Bb5+

Also there’s 3. d4 Nxd5 although I’m not a very big fan of these lines since black tends not to have any space. But some people play it.

I wouldn’t want to play this opening myself really, especially since once your opponents start prepping for you, you may have major problems equalizing against masters. But if I had a student playing this at the club/class level with success I wouldn’t insist on them changing it.