It raises way too many questions about where to draw the line for the concepts of control (as in the above example), detachment, and what is natural, and I don’t like inherently ambiguous worldviews because they become way too prone to highly subjective interpretation (especially true for stoicism when you try to apply it to the context of political and moral questions) and they create too many discussions that aren’t worth having (or, are only worth having with better-stated claims/philosophies that emerge from a mental model of the world that corresponds with what science confirms).
I think it helps to see stoicism not as A philosophy in the modern understanding as something akin to a religion/worldview you have to buy into wholesale. It's more a practical guide how to live with many great ideas and some that are outdated/unrealistic. Engage with the ideas on their terms as 2000 year old thoughts and see how they do or do not serve you.
My experience with stoicism so far has been fairly different, but it might be because I'm cherry picking things I like. One thing I have enjoyed about it though is how objective it seems rather than subjective. I have a feeling if I delve more into modern stoicism I'll find more of what you're talking about.
> concepts of control
This one seems to me to be something like:
1. Anything external is out of your control
2. Anything internal is in the realm of possibility to control if you're healthy and willing
3. Having the faculties to control yourself is a gift/incredibly fortunate, and to hone that ability is very virtuous
If you lack control it's either because a) you're unable to due to some affliction like mental disability or sickness (not lacking virtue) or b) you don't practice enough (lacking virtue). I suppose there's room for a c) both a and b, too. This is where you're right - this becomes very subjective. There's a blurry, blurry line between hard, limiting disabilities and resolvable illness. I would say though that each of us can only do our best, and believe others are also doing their best. To split hairs on why people act the way they do would be pointless. Instead we should focus on supporting them to do better if they evidently need the help.
> create too many discussions that aren’t worth having
This has seemed to be something that's resented by a lot of classic stoics. Take Marcus Aurelius in Mediations here:
"Waste no more time arguing what a good man should be. Be one." - 10.16
"Be not a man of superfluous words or superfluous deeds." - 3.5
"[I’m grateful to the gods…] that when I had my heart set on philosophy, I did not fall into the hands of a sophist nor sat alone writing, *nor untangled syllogisms* (emphasis mine) nor preoccupied myself with celestial phenomena." - 1.17
Mind you, Marcus (to my knowledge) never self-identified as a stoic, though he was surrounded by and taught by stoics and his philosophy seems to pound on the 4 cardinal virtues relentlessly.
Here, Epictetus alludes to the futility of certain trivial diversions in philosophical debate:
"[...] What Nature is, and how she administers the universe, and whether she really exists or not, these are questions about which there is no need to go on to bother ourselves." - Fragment
"Be mostly silent; or speak merely what is needful, and in few words." - Enchiridion, 33
I think the problem of trivial diversion, specifically when it comes to subjectivity, is a widespread problem in philosophy and not necessarily specific to stoicism. I do think that debating subjective interpretations without some common good in sight or at hand is contrary to stoic philosophy.
Maybe what you're saying is undeniable evidence of the subjectivity being a problem, though. I certainly can't argue that, and I know others struggle with that too. It could be that I'm just taking what I like and silently rejecting the rest. I think this is why what many stoics did in taking what made sense from other schools of thought, purely because it seemed truthful, is still wise today. Many stoics weren't even opposed to slavery for example - it's clearly a product of a different time. I'm not sure that I'd ever identify as a stoic either, but I do enjoy a lot of what it has to offer so far. It's fascinating to see how much we're like people from 2000 years ago, too.