I can name at least three situations where having those attacks is to the felar's detriment:
Fighting a sword or dagger spec (extra riposte/concealed)
Fighting a porcupine (obviously!)
Sparring (claw attacks do a lot of damage)

Those are especially painful if you're a spear, staff or polearm user (since wearing a shield, which prevents claw attacks, is not an option). And it makes no sense for felar to be unable to NOT make extra strikes with their claws when it's relevant.

Please?

Felars are great with spear/polearm and such because of their bonus, but that bonus comes with a few noticeable drawbacks. Porcupines are one of them. And honestly, they are about the only one. Using a shield as you note is a good way to mitigate offense strikes, if you are of a mind to do so.

Sparring is easy, equip low value weapons (I guess you can't hth spar as readily with a felar but that's about it)

Against sword and dagger specs, having extra attacks is bad for everyone, not just a felar. Consider it more of a perk of those than a drawback of the felar though.

Giving a felar the ability to toggle just gives them an even bigger advantage to their claw attacks. I would probably not want to have second/third/fourth attack practiced against sword or dagger specs, but I practice those skills because of all the other times those skills are useful. The same goes for claw attacks. That there are some rare scenarios where having that bonus possibly work against you, I have to believe, is part of the balance and design.

Toggling whether you use 2nd/3rd/4th attacks, etc would probably introduce unnecessary complexity.

I *could* see the ability to toggle whether you attack with a dual-wielded weapon, or simply use it defensively. Obviously if you gave that to felar, you'd have to give it to everyone else too.

In that case, felar claws would count as the dual-wield.

I'd rather see more moderate disadvantages against several types of opponents than be utterly dominated by one rare specific build (porcupine) that is useless against everyone else but me.

Plus, the specific flavor is kinda sad. It's fine if I'm an arial and some invoker pwns me with engulf, or I'm a drow and I get splattered by a backstab with Heartseeker. But the spines... I can't help but rip my face off biting a cactus?

Hi, come impale yourself to death trying to punch me Mr. storm giant.
Wouldn't he just pick up a rock or something to smash it with?
Of course, maybe it's a rabid enraged porcupine that relentlessly assaults its prey and charges into them to impale the people. It can ball up and throw itself at people like Blanka.
Or make it like Pwent, it impales you and then shake violently tearing you to shreds. Move it into an offensive form though.

Truth is though, I really have just never viewed the porcupine to felar as common enough to consider it in need of adjusting. Porcs are not that common, and as you note, it only really shines against mobs and certain builds. Great for raiding/retreiving some of the cabals though.

I've met at least 3 just in my current character's time.
And if moved into offense, it would become way more common as people pick offense all the time.

Fine as it is.

And they should, in some situations.

That doesn't make them immune to those situations.

So I have to believe the design of each is intentional, as are the potential drawbacks of not being able to toggle them on and off for those who can not do so.

This same toggle on/off ability would have to apply to every automatic skill in the game. And it really doesn't seem all that worth it since it would be so highly situational, and really only work to completely nerf a few combat scenarios.