A friend who was mentioned in that post showed me that they were getting cursed at, but from my perspective there are many points that are hard to understand, so I'm joining and posting.
Fortunately, I have photos that I took and photos that my friend took, so I'm trying to explain together with those photos.
First, you asked "Why would you block the way and place it against the wall where the fire extinguisher is when there's space on the inner rack side?" so I'm answering that.

As someone taking the subway with a bicycle for the first time, the bicycle rack appeared to be completely full,
Since the rack was full, I thought I should lean my bicycle against the wall, so I did that.
Although I got into cycling in March this year, I'm aware that the bicycles in the photos are quite expensive bicycles,
Even if asked to do it again, I don't think I would insert my bicycle between other bicycles.
Also, you said our group blocked the way, but I find this part difficult to understand as well
You wrote it as if "group" would be at least three or four people, but there are only 2 of us
As you can see in the photos, at Paldang Station, we tried to stack two bicycles against the wall inside the entrance as much as possible so as not to obstruct passage.
The rear wheel did not go over the fire extinguisher, and there was enough space between the fire extinguisher and the entrance (although it's not visible in the photo, there is a driver's cabin door and sufficient space).
I did not think it would obstruct passage
And another difficulty with placing it on the rack was,

There was someone holding a bicycle by hand at the end of the seat on the opposite side of the rack.
If you look at the photo, you will see a wheel behind the rear wheel of the bicycle standing in the rack, which is the front wheel of the bicycle standing next to the seat.
The wheel visible at the opposite entrance is the rear wheel of that bicycle. I believe you can guess how the bicycle is standing.
I also thought the bicycle rack was full, and since that bicycle was blocking the middle corridor, I naturally placed it against the wall.
The fact that there was still enough space even after placing it against the wall is evidenced by the MTB rider with wide handlebars who boarded after us.
No matter how much I think back on it, no matter how much I reconsider, it was not a situation where boarding the subway was impossible.
There was enough space for a bicycle rider to stand with their bicycle between the 2 bicycles we placed against the wall, the bicycle being held by someone sitting on the seat, and the bicycles standing in the rack.
Why on earth couldn't you board? Before blaming us, I simply cannot understand the fact that you couldn't board that car.
What's even more incomprehensible is that if you had to wait 30 minutes for the next train, it would have been better if you had told us.
The way you have your bicycle standing now is inefficient.
It's obstructing me from boarding after you. Please stand it like this.
If you had said something like that, despite there being enough space, I would have apologized and repositioned the bicycle as you instructed.
It seemed like the person was wearing cycling clothing and waited with us the whole time
To be honest, you didn't even show any sound or sign while boarding from behind, so I didn't even know you were there at that moment.
If you had at least sighed, I probably would have done something wondering "are we doing something wrong?"
You didn't say a word there, but then you posted on an internet community asking for people to curse us, which is absurd.
Looking at your exchange in the first comment of your post, it seems like you posted it for us to see, and it would have been better for both of us if you had spoken to us there and boarded together and returned home.