I don't see any dramatic contrast between "these types of abilities" and "4e-esque powers".
I'll just leave this at you have your opinion and I have mine...
The manticore doesn't. The bone devil doesn't. The cambion has spell casting and a charm ability - nothing within cooee of the Chained Cambion of 4e's MM3.
The Manticore in 4e has a claw attack, spike attack and multi-attack... and can shift between attacks. The 5e manticore has a claw attack, a ranged attack and a multi-attack, and can already move between attacks because of 5e's rules.. it can do everything the 4e one can with less verbage.
The Bone Devil of 5e has Telepathy, Devil's Sight, Magic Resistance, immunity to non-silvered weapons, a sting which uses poison, multi-attack and has the option of attacking and grappling with the hooked polearm.
The 4e Bone Devil can attack with claws, poison sting, multi-attack, has an aura of fear, impose -5 to hit as a minor action and an aura of obedience...
Again not seeing a big difference in number of interesting abilities...
Wait so you're comparing a MM 3 monster (after years of development experience) with the base cambion of 5e... come on now let's compare like and like... Cambion Hellsword from MM1 to the Cambion in 5e's MM1...
4e: Hellsword, Whirlwind Charge and Triumphant Surge
5e: innate spellcasting, fiendish charm, multi-attack, fire ray, and spear.
5e seems like a way more intersting monster to run.
The umber hulk has one interesting ability: its gaze. And the bulette has its leap. And at least of the pre-released non-legendary creatures that I've seen, these seem to be at the more complex end.
The Umber Hulk in 4e has one interesting attack... it's gaze. And the bulette in 4e is about the only one I see where it has more interesting options (and is more complicated) than the 5e version and that's only by a small margin.
(Putting to one side the heavy reliance on spellcasting to give creatures interesting abilities, which has its own issues that have already been well-articuated across multiple threads.)
What does this matter? If an ability that makes the creature interesting and fun to run exists why does it matter if it's a spell... see this rings of "It's not 4e"... as opposed to "the monster is boring".
Part of what is interesting about the kobold abilities, which I think has the potential to make them more interesting than the umber hulk or bulette, is that they interact. So (for instance) players have an incentive to have their PCs bring the fight with the kobolds into the sunlight so as to negate their advantage for pack combat. And, conversely, kobolds fighting in the sunlight will be trying to bring their pack tactics to bear so as to negate their disadvantage.
So PC's trying to avert their gaze in the case of the Umber Hulk... or find something reflective to view him in, or... well you get the picture isn't interacting? Making sure you don't clump too many in your party together but also trying to work together so the bulette in 5e can't use deadly leap isn't interacting? I guess we just have very different ideas of what interacting with something is then.