That's true, HL2 does have some great vibes, but Water Hazard and The Coast levels just seem to go on for much longer than they should, particularly some parts of Water Hazard where you're literally in a trench and don't have much to look at so it's just driving down barren concrete tunnels while holding W.

There are some memorable moments, like everyone remembers the brick stack that falls on the player, and I particularly liked the more industrial areas of Water Hazard, and there are also some that use the driving mechanics more like the boss fight with the helicopter, but IMO the vehicle sections in HL2 are very much the "On a Rail" of HL2.

oh and also in Water Hazard while slowly making your way to Black Mesa East you get to watch the sun go down with each level transition and that looks/feels cool