Yup, you're spot on. Kobolds, Orcs, and such have HP bloat, higher bonuses to hit and damage to compensate for the increase in player power. That being said, the CR as presented in the 5e books is worthless. All it has really done is make PCs feel invulnerable (they can still mow down orcs and kobolds at low level), and at levels 3-10 walk all over equal CR threats. And sure, the DM can adjust, but in Basic, a 1 HD creature is about on par with a 1st level fighter (both d8 HD). And a 4HD creature is about on par with a 4th level fighter.
Whereas a my character in 5e out to 4th would be 36 HP, all of its 3rd level Battlemaster Abilities, an ASI or a FEAT to further increase its ability.
That Basic Fighter? 3d8 more HP, and Thaco 16.
But yes, the threats of equal "level" are more equal. But it also seems like a vicious circle now where all the choices and abilities further push the curve up, and the monsters have to be increased to compensate. Heck, an Ad&d Ancient Red Dragon has 88 max hit points. A 5e Ogre sits at 59 (average, 91 max) and a CR2. Appropriate for a party of 4 Level 2 characters. I find the combats and monster stuff in 5e tedious as a result. But that's me, and YMMV.