- Tactics skill in Heroes 3.

And which ones?
Eight slots.
Logistics, earth and air magic, and wisdom are definitely needed.
By the way, I sincerely believe that in the early days of the game, tactics are the only substitute for air magic.
Attack and defense also wouldn't hurt.
So, that's 6 slots out of 8.
No argument, tactics are useless in buildings. But logistics is also useless there:)))
But for breaking through archers, for protecting your own archers, it's simply invaluable. Tactics are an extra half-round before the start of the battle. And half a round is quite significant...

At the very beginning, it may be useful, I don't argue. When the character is developed, it is much more important to make the first move than to position them. With an expert in air magic, almost all units reach the battlefield from the first move; the main thing is to have the right to the first move. With equal forces, moving your units forward simplifies the task even further, and hiding any archers or other units behind others doesn't solve anything.
And I also want to say, let's not belittle anyone! Who knows more, who plays better, is determined in a real battle. And then you can say whether someone is a noob or not. Although it's not worth saying that, it's not polite.

Added 7 minutes later

I think the higher the skill, the more tactics are needed.

I would say the opposite, the higher the skill, the less tactics are needed. :D This is not entirely true, but saying that it becomes more necessary is also not true.