You obviously don't understand what charms are or how they work.

Charms are specifically designed to have abilities that aren't actually worth the CMC printed on the card. Quote from the article: "It turns out that one small effect might not be worth a mana, but the option between three small effects was."

Temur Charm is not and never has been a "3CMC Mana Leak," because a 3CMC Mana Leak would be overcosted. The mana cost comes from the fact that you are given the option to use the charm as a Mana Leak, as a fight spell, or as a Falter spell. You aren't just paying for the three abilities - you're paying for three abilities and the ability to choose which of them you use.

Again, because you clearly don't understand the card, it's actually a really neat card for this reason: the major weakness of counterspells is that they cannot deal with spells once they have resolved. In fact, the inability to destroy permanents at all is a major weakness of Blue cards in general.

Temur Charm, however, in a deck built to utilize it, can deal with (creature) spells that have already resolved. In fact, this makes it pretty unique among counterspells, and gives it a versatility that tempo decks need.

The key here, though, is that your deck has to be built to utilize it. You can't use Temur Charm's fight mode in a deck full of 1/1 mana creatures. I agree that Temur Charm is a very finnicky card that requires a bit of cleverness and luck to use. As you perfectly demonstrate, it takes a little bit of thought to understand how to use the card properly.

Again, though, good luck grinding those tournaments with the latest Tom Ross budget deck. What is he on these days? Goblins? I'm sure you'll do fine with what he puts together.