Exactly. Although I wouldn't personally think he built Tesla to potentially support Space X. He gave it the same 10% slim chance of success when he started as Space X, and he allocated to it roughly the same amount of funds ~ 100mm to each (for a total = to his entire net worth). So by going after Tesla as well he significantly hindered his chances of succeeding with Space X as that narrowed funds available for that project by half and if he had failed the fourth Falcon 1 launch it would have been game over for that. If all he cared for was Mars, it would have made a lot more sense for him to throw 200mm into Space X and greatly increase his chances of successfully developing an orbital vehicle and grow from there in partnership with NASA.

I think generally his core vision or at least core mission statement is to help humanity scale and survive and he'll allocate funds / explore opportunities however he seems best to achieve that.

One pillar of that vision is planetary colonisation to act as a hedge / diversification against a single planet extinction event. The other is making Earth life sustainable hence sustainably electrifying all forms of fossil fuel use cases the founding venture for that being Tesla.

All that said, I have a hard time at this point imagining Elon ever being resource constrained for his goals. He just has too many promising potential revenue lines. Hell, he could maybe fund all of it one day with a single asteroid capture for all we know.

His core constraint is time and he'll do whatever he can to speed things up. Crew Dragon was an important deliverable but ultimately obviously can't be expanded to serve the final vision and it makes sense to quickly move on with all the additional knowledge gained from the effort as a huge benefit.

Starship development should make the next few years just fascinating for us space nerds.