Wildly different. One of the biggest things at a small company is that you can wear multiple hats to solve a problem and not step on anyone's toes. Need to play PM, backend engineer and data scientist to get a product shipped fast? No problem, and you'll be seen as a person who can get things done by leadership (if you make sure to keep your work visible).

The main divide I've seen between what makes people happy in one or the other style tech company is whether they really enjoy solving problems or doing their job. If you want to check in, do only what is technically required of you and get out, then big tech corp is for you. If you are mainly interested in finding solutions to problems and you are happy to employ whatever is necessary to do so, you'll have more enjoy small companies much more.