They both are spending tons of money to spread propaganda to influence public opinion and elections is the first and easiest to point out.
They also both own major news outlets that defend them publicly and are very influential of public opinion.
Both have through their businesses received government subsidies, in effect having us tax dollars go to their pockets. This cycle is repeated through the influence they buy by spreading propaganda, using lobbyists, using money as a tool within the government apparatus to generate more money for their companies and in turn for themselves.
If you don't think that influencing public opinion matters in a democratic republic, I invite you to learn about Hitler's rise to power, Joseph Goebbels, the Nazi party in Germany, and the holocaust. Using the same propaganda techniques used by the Nazi party, misinformation is used to influence public opinion. This is especially true on Elon's Twitter, but Bezos has used the same techniques to attempt to union bust.
Millions of people died as a result of the propaganda campaigns of the Nazi party. I fear history is about to repeat itself in the usa.