"of his era" ...
If Tycho Brahe had lived through the modern era, where we've seen 50+ years of orbital space flight, have imagery of the whole Earth every 10 mins through weather satellites, have seen over 20 humans go to the Moon and back .....
Do you think he would bother doing his experiment?
You just answered the question of why the source is old. Astronomers wouldn't study something unless they felt it was a matter of question or contention. Congratulations?
So you don't think those things I quoted are a matter of question or contention, then?
I happen to think that it is a matter of question and contention, but that is not what the educational system teaches. Astronomers like Tycho Brahe studied these things back then because it was an open question. But today Astronomers are taught and told that it has all been resolved. They don't even consider to study or confirm these types of things today.
This is why the Flat Earth Society is the greatest free thinking organization on earth. The movement questions the unquestionable and challenges the unchallenged.
The key point on Tycho Brahe's work is whether the Earth orbits the Sun or vice versa. He knows the Earth is round and his observations rely on it. He might dispute the spin but he agrees with the shape.
Do you accept his findings?
Every Astronomer bases the assumptions in his or her work on the current dogma of the day. If the shape of the earth was not something under question or contention, it would not be studied. The earth's rotation or geocentricity is not studied today, which is why there are no modern attempts. It is a "closed matter". In the mid 1500's, the earth's shape was a "closed matter," although there were still debates about whether it was the center of everything.
It is not a coincidence that Tycho published his findings around the time Copernicus did. These studies were the result of world wide debates. Tycho didn't decide to do it on his own. If the shape of the earth were under question instead, Tycho would have studied that.