Hi, welcome to content that is moderately challenging. To put things in perspective, I would estimate there are currently 6 to 9 encounters more difficult than Garuda EX, and someone has beaten all of them. Also, there are 7-player groups that "sell" runs through all of the extreme primals where the buyer can just die right at the beginning and they consistently win with 7 people instead of 8.

It seems hard because your group (probably including you) isn't that good at it...yet. Practice, experiment, fail a lot, improve your gear & items, and stick with the same group of people so that you learn together. People that do this accomplish far more than those who do not.

If you can't/won't do the above, then get accustomed to there being some encounters which you just will not win. Those encounters are designed to keep the more accomplished players interested in the game.

There IS such a thing as an encounter that is too hard. See Twintania right after 2.0 release: it took a very long time for even 1 group to beat it, and SE nerfed it immediately after. Garuda EX is not on that level.