bachutz of the beged, what makes you think he's saying bachutz of pants? Rashi says the Gemara is saying it must be a fringe off the corner of the beged and the MGA tries to extend that to disallow strings tucked into the corner of the beged because they don't come off the corner like a fringe. This is completely irrelevant to pants.
@avromie7 any reason why this shouldn’t apply equally to someone wearing the beged in?
This is the same as the MB he decries hiding the tzitzis, but there's no indication that that applies to us who for whatever reason keep the beged inside our shirt. Once that's ok, it's not "hiding" to not take the strings out.
Uses the drasha of אין ציצית אלא יוצא.
Also only talking about if sticking into the corners but if all hidden in the pants he’d be totally and completely cool with it?
I think
@shulem92 mentioned that it's common to be referred to as teluyin umegulin because they were only talking about people who wear the beged out and that was the way to refer to it.
As I said before, the Gemara about yotzei definitely can't be compared to when the beged is under the shirt.
In summary, there are 2 common complaints.
1. Not to put the strings in the corners which the MGA doesn't like because of yotzei.
2. Not to hide the strings because of bushah as it's a bizayon to take the mitzvah and hide it. There is no indication this is talking about us who wear the beged in. I'm not sure why we wear the beged under our shirts, but not sticking the strings out is not the same as sticking them in.