Larger companies not only offer better compensation, but usually offer much better career development, responsibility growth, training and “learn by doing” opportunities.
The startup will promise you won’t be blocked by bureaucracy and as an early hire you can lead the design. Total lies. The bureaucracy and dysfunction will be even worse and probably involve a bunch of immature egos and “the design” will be endlessly compromised to get each successive round of diluting funding that yokes you to more and more traditional management bureaucracy through VCs.
After experiencing the special hell of unrestrained founders who don’t know what they are doing and nepotism hires all through middle management, most people quickly realize it’s an insane trap and wish for the comfort of large firm bureaucracy, where at least there’s some minimal policy protection against sexual harassment or cultivating alcoholism as a company value or generally grinding unwitting young people into the ground with 80 hour weeks.