First of all, maximum of 2 angels, trying to build angels on normal templates with Castle is stupid even in TE.

First of all, it's not stupid or not stupid, but the question is whether there is money for it. If there is money, then it's not stupid at all.

Secondly, after building this, you also have to buy them, which adds hassle. That is, while the player who built angels is gathering money to buy them, the player who built horses on 121 has already bought everything and starts upgrading.

Secondly, sorry, but don't talk nonsense, 2-3 angels cost 6-9 thousand, this whole mishmash of horses, Marksmen, Crusaders, and pokemons costs about the same, and even considering the cost of building upgrades, much more, + time for construction and the hassle of moving troops for upgrades. A hero with angels runs around doing his own business at maximum speed and doesn't bother. Fact ;)

But even if there is money to buy them, let's compare the effect:

2 angels + 7 Monks
vs
6 horses (usually upgraded) + additional Crusaders, Marksmen, Pikemen (from Castle).

Significant loss for the first option in both hits and damage.

Now here's where it gets interesting, the second option of course dominates when breaking through walking fat monsters like golem hordes, but it methodically melts against shooters and when taking serious objects (Dragon Fly Hives for sure, Griffin Conservatories are no joke if there's no mass slow either) and generally against more or less serious monsters, etc., etc., there are plenty of examples. Angels, when used skillfully, have a strange habit of staying alive, even if with a few hitpoints at the end of the battle ;) . Fact.
Furthermore, there are almost always at least a couple of Griffin Conservatories on the explored territory, and there is a good chance of forming a strike stack of angels, for example 5 angels are an order of magnitude more effective than 3, and later in Dragon Utopias, the more angels there are, the less chance that the dragons will jump on them rather than on the meat shield. Fact.

Significant loss for the first option in both hits and damage.

Which is more than compensated by the attack, defense, and speed, as well as the health of the angels, as I already said, with skillful handling, angels usually survive where the second option loses by a little bit.
Conclusion - if you have the money, you can build angels in the fort without a second thought, and if the town is generating income, it's generally ideal. Try to disprove that ;)