As DB pointed out with the "America's Team" moniker, if a team has a name put on them, fine, I feel that is the way to get a nickname.
When this Texans nickname came about it was self-produced (bad), and it was a horrible name (worse). Also my thinking at the time, mainly due to the fact that everybody seemed to have this need
to name them, was why? Do they have
to have a nickname? "Texans" was fine for me in the interim until a bonafide name came along that WAS them.
The best example I can think of was the 1985 Chicago Bears defense. Ok, "Monsters Of The Midway" but that was a name given the team
back in the 40's, or right around there. They just recycled the name. Imo, recycled names are not authentic moniker's for an accomplished defense. In my view that defense, football's equivalent to boxing's Mike Tyson in both ferocity and longevity (relevance works too), had no name, not even "No Name." But to this day just say "'85" and "Bears" in the same sentence and immediately you think of terror in the eyes of the offensive offenders.
The Texans are the Texans, nickname or not. For my money, name me, for I will not be so pretentious as to name myself.