Environment and control (true ownership) can easily turn 1x into 10x, I'd say. Not saying I could churn out Rollercoaster Tycoon but I bet I'd look, by every metric both reasonable and unreasonable, a hell of a lot more productive working on a game solo with 100% control of all decisions and not having to fret about having something to report in standup every day versus... normal work.
Productively building and finding the right thing to build to be successful are different things, and one can be good at either while being terrible at the other.
