It is not any skill check, it is any skill check using the chosen ability. This makes it far less flexible IME. For example you give it to the Rogue before he checks out the chest. You give it to him on Dexterity, well he can't use it to do a Wisdom (perception) check to see if there are traps or an Intelligence (Arcana) check to understand what the magic Glyphs on it are for. IME this makes it far less flexible than the 2014 rules.
That's not quite right.
You pick a skill (like stealth or athletics) not an ability (which could apply to any number of skills). For the duration of the spell you add 1d4 when using that skill.
For situations where you need to use a skill more than once, it's much better, it only has to be cast once as opposed to spammed (which may be problematic depending on the situation)
But when you're not certain which skill will be useful, it is less flexible, because the old version allowed the target to pick any one skill usage within the duration.
So better or worse, depends, it's almost a different spell really.