why does no-one play the 4 knights these days?
You may be on to something. Fedoseev knocked out Nakamura from the World Cup when Naka misplayed the 4 Knights.
4 knights is actually fine and offers quite a lot of options.
It's just not so rich as Spanish and Italian but that is important for IMs and GMs, not for us.
For us the simpler the opening is the better.
And there are no drawish openings unless:
1)Both have equally deep understanding of the opening, the middlegame and the endgame(happens only in high level) or
2)Both are equally ignorants(happens all the time).
3) You play a line that leads to a forced draw(perpetual check or 3 fold repetition)
In all other cases there are a lot of winning chances for both sides.
This.


Well, four knight is good. it's a safe positional opening. Maybe it depends on the view and attitude of a player. Players which are aggressive-attacker type will definitely avoid it because it is dull for them to play. For those players who are playing on defensive mode well four knights opening has a lot to offer.

The Spanish is an extremely positional opening...

There are a lot of Italian Games, Vienna Openings, and Bishop's Openings that transpose into the Four Knights, which is a solid opening and, considering most games are lost by giving away more pieces than your opponent does, the Four Knights promotes overprotection.
The straightforward four knights, 1 e4 e5 2 Nf3 Nc6 3 Nc3 Nf6 can be transposed those openings or into the Spanish Four Knights (4 Bb5), the Scotch Four Knights (4 d4 exd4 5 Nxd4), and other openings including some wide-open ones like the Belgrade Gambit (4 d4 exd4 5 Nd5) and some systems that can confuse an opponent like the Glek (4 g3), which has developed a large following.
Here's an Italian Game where I transposed into the Four Knights and decided to Castle Queenside, then Pawn Storm the Kingside: