So this kinda runs in direct contradiction to this, which you said one post before:
No, it is not a contradiction at all. You are confusing an FBI report in the day(s) before the protest with the 15,000 attending the protest itself.
The one-line internet post "Get violent. Stop calling this a march, or rally or a protest" does not speak for all the people attending the protest and most of the 15,000 were not involved in the few hundred rioters who entered the Capitol. Anybody could have written that post.
To suggest all 15,000 went to D.C. to storm the Capitol is nonsense. Especially with your claim that they sought to kill those in line for the presidency. Most of those in line of succession were not even at the Capitol.
So what I don't understand is why you made the assumption here after reading and quoting the NYT article where they literally say not to think of this as a protest or riot"
"They literally say.." Who is they? It is a one-line post on the internet. You don't know who posted it, if they were actually involved in the protest, and certainly no clue whether the other people attending agreed with those sentiments.
It was probably posted by somebody on JPP.