If every wealthy country had a frog to represent their culture of taking care of workers (strong unions, workers rights, vacation days, not having healthcare tied to their employment, maternity and paternity leave, equitable pay etc), there is one particular frog which most would describe as having had its brain removed.

From the wikipedia article linked to just below this reply, it says that the first such experiment is as you described. But then goes on to say:

Other 19th-century experiments were purported to show that frogs did not attempt to escape gradually heated water. An 1872 experiment by Heinzmann was said to show that a normal frog would not attempt to escape if the water was heated slowly enough, which was corroborated in 1875 by German scientist Carl Fratscher.

I don't see the point of the experiment with the brain removed, but given that they did the experiment with intact frogs as well confirms their original hypothesis.

However, later on in the article, it's been disputed in recent years: as the water is heated by about 2 °F (about 1 °C), per minute, the frog becomes increasingly active as it tries to escape, and eventually jumps out if it can. Earlier it also says that frogs put into already water just die (not mentioned, but presumably from shock) and so don't have a chance to start attempting to jump out. I imagine humans dumped into boiling water would have a similar response.

Frog boiling seems like an active research field. I wonder what the social dinners are like at their conferences.