Lenny Rachitsky is one of the OGs of product, having spent over 7 years at Airbnb as a product lead he left to start his newsletter, find it here. This has scaled to thousands upon thousands of readers and is one of the most popular newsletters on Substack. Lenny is also an extremely active angel investor with a portfolio including Figma, Sorare, Clubhouse, Vanta, WhatNot and many more incredible companies. If that was not enough, Lenny also has the best course on product management, check it out