This guy is just either bad at the game or doesn't know how to play it. You can glide for hours without having to hit the ground, and very rarely get stuck on anything if you know how to play. Of course you can't walk to many places. Nobody buys open world games, and expects to walk to the objective. Do you buy GTA 5 and complain that you can't walk everywhere quickly? NO. You are overstating the quality of the last games. They were good, but no where near Arkham Knight. They added new game play mechanics that are fun 90% of the time, and improved everything from the previous games. The story most of all, the narrative of the last 2 games was way too twisty. And as for boss battles that is a personal preference. I think the boss battles in the last 2 games were the weak points, and they are the weak points of this game. Boss battles almost never work, the only game I can remember them being fun was the MGS series, and Metroid.
To each their own, but don't let anyone sway you from the game. You are missing out on the best of the arkham series IMHO.