Using 2021 figures, there are 128 companies earning $3 billion or more, out of the S&P 500. Including Berkshire insurance, BHE (energy) and BNSF Railway, Berkshire is the largest owner of 11 of those 130 big giants (128 plus BHE and BNSF).
The letter has grown shorter in recent years. From 2010 to 2016, those were over 20 pages. From 2017 to 2021, those were 10+ pages. The 2022 letter is 10 pages.