Replacing an ability with another via archtypes

Question

In pathfinder. When I take the archetype of a Hungry Ghost Monk, I get the following:

Punishing Kick (Ex)

At 1st level, a hungry ghost monk gains Punishing Kick as a bonus feat, even if he does not meet the prerequisites. At 10th level, and every five levels thereafter, the monk can push the target of his Punishing Kick an additional 5 feet (10 feet at 10th level, 15 feet at 15th level, and 20 feet at 20th level). At 15th level, he can instead choose to push the target 5 feet and knock the target prone with the same attack. The target still gets a saving throw to avoid being knocked prone.

This ability replaces stunning fist.

For a third level feat, I found Crushing Blow, which states:

Crushing Blow (Combat)

Your focus allows you to smash your enemy’s defenses.

Prerequisites: Improved Unarmed Strike, Stunning Fist.

Benefit: You can make a Stunning Fist attempt as a full-round action. If successful, instead of stunning your target, you reduce the target’s AC by an amount equal to your Wisdom modifier for 1 minute. This penalty does not stack with other penalties applied due to Crushing Blow.

I am just unsure enough on the wording to know with certainty myself, but did swapping out Stunning Fist for Devastating kick also shut me out of all the feats that need it as a prerequisite? Or because it's an archetype, to I just replace the wording?

If so, this just seems like another reason to never take archetypes. All the feats are generally written to take into account class abilities obtained by the generic class. So Stunning Strike, Stunning Pin, Crushing Blow. All locked out because you went an archetype? It seems like you are giving up so much than just a swap of abilities

Answer 1

Yes...

You don't have the prerequisite for the Crushing Blow feat, so you can't get it the same moment a non-archetype monk would. It's part of the price you pay for the archetype - you get weaker in some aspects and stronger than others. As to whether it's a fair exchange - that's for you to decide when choosing whether or not to get an archetype.

But No.

You can still pick up Stunning Fist, you just need to spend a Feat slot like anybody else would, and meet the prerequisites like anybody else. Given the BAB +8 requirement, it would be level 11 at the soonest - making it level 13 to get Crushing Blow unless you have the opportunity to Retrain a feat.