At the beginning of Bitcoin, every newly mined block (about every 10 minutes) creates 50 bitcoins. This is called the block reward. About every 4 years, this number cuts in half. Therefore, the peak extraction rate was about the first 4 years of Bitcoin's existence.

In fact, it was from 3 January 2009 to 28 November 2012.

Note that one block is mined about every 10 minutes. The number of miners is irrelevant. The speed of the miners is irrelevant. The system automatically adjusts itself so that one block is mined about every 10 minutes. That is the only reason why mining requires a lot more computational power than it used to - you are competing with a lot more people.

At the beginning of Bitcoin, every newly mined block (about every 10 minutes) creates 50 bitcoins. This is called the block subsidy. About every 4 years, this number cuts in half. Therefore, the peak extraction rate was about the first 4 years of Bitcoin's existence.

In fact, it was from 3 January 2009 to 28 November 2012.

The block reward includes both the block subsidy, and the transaction fees of transactions included in the block, so miners still get bitcoins, but they are not newly "extracted" bitcoins, they are bitcoins that someone else has paid.

Note that one block is mined about every 10 minutes. The number of miners is irrelevant. The speed of the miners is irrelevant. The system automatically adjusts itself so that one block is mined about every 10 minutes. That is the only reason why mining requires a lot more computational power than it used to - you are competing with a lot more people.