To be fair to BE focused folks the Web exploded from being a bad document environment you did ugly hacks and cargo-culting on to make something interesting, to an actual platform at quite a high speed.
And additionally to this during the time it became viable a lots of FE folks still had to continue battling IE6 in their daily lives so online documentation still lagged and had a clear smell of the cargo-culting. Heck even today you see people complaining about Javascript here on HN.
But being left behind today, you gotta blame yourself. Early realtime Google-suggestions using AJAX came already back around 2005 (?) and if you didn't take notice and still missed people were doing decent realtime games by 2010 you were doing your best to live under a rock.