Are there any reason to delay leveling up?

To avoid stronger enemies probably not? Note that Skyrim does have level-scaling in regards to the enemies you encounter, it is just a bit more constrained and does not go overboard with enemy equipment as Oblivion did.

However, much of your power growth in Skyrim comes from Perks which you only get when you take the level up. So just increasing skills without taking the level up, does not help you much as it did in Oblivion. I would say that if your skills are at a level that you do not have something useful unlocked to put a perk point in, then this might be a good time to delay the level up a bit. But it is no way mandatory or has the same effect on difficulty as in Oblivion.

There is one more valid reason to delay. When you level up you restore all your health, magicka, stamina. So saving level ups can be used to fully heal you in difficult fights.

As you say, unlike Oblivion, there is no statistical reason to delay levelling up. You're not going to have worse stats by levelling as soon as possible.

However, it is possible to level up with non-combat skills (Smithing, Speech, etc) which will still count towards your overall level, but not actually increase your combat effectiveness. This can potentially cause problems if you start getting stronger enemies, even though you're not doing any more damage.