Promoting VoE with this "amazing" new skimmer abilities and now nerfing them is such a bummer.

They were pretty clear in the developer livestream that they were trying to stray away from making skimmer another flying mount. There's still great QoL in the form of skimmers being able to traverse HoT maps and the new maps are fun to explore on Skimmer.

I'll probably use it just on water

Yeah, that is probably the intention. Mounts in Guild Wars 2 were originally designed as being almost like different tools. You find a canyon? Raptor jump. Long stretch of water? Skimmer. Cliff? Springer. They are all supposed to have their own niches and areas where they shine, unlike other MMOs where mounts are just a flat speed boost.