Sometimes they get an equal share. Other times they are just more credible than you and can rally the other shareholders. Other times they threaten other consequences simply through their influence. They don't need a legal mechanism to force your hand.

Never been an entrepreneur myself, but was an employee of a startup in an accelerator and have worked for two others.

My contract had things like "investors majority" and supervisory board with lots of power where I only had 1 vote.

Those 2 things together could force me to do almost anything if they really wanted.

It's all in the details.