It’s healthy to look at all financial incentives as a balance of risk/rewards.

Many people contribute to FOSS out of interest or as a hobby with no expectation of financial incentive at all.

But you can approach FOSS with an intention to commercialize. For example, I once had coffee with a developer named Ross Mason who started an FOSS project which became a commercial success called MuleSoft and sold to Salesforce for $6.5 billion.

When you consider dedicating your time and effort toward FOSS there may be no commercial opportunity. You may discover a commercial opportunity along the way. In that world you’re taking on personal risk, but if you figure out something new/novel/interesting/valuable you may get substantially rewarded by the market.

If you work for a company who pays you (and in which you have no ownership of the company) then you are taking minimal risk and getting certainty of the reward you negotiate (your salary).

Most software projects live on a spectrum of maximal certainty, but minimal surprises to the upside or minimal certainty and maximal possibilities of upside. Your choices about where to place your effort depend upon your desires/needs/life circumstance. It’s always a spectrum and there is not one universally correct answer.

But if someone is paying you a salary, you should realize that they are likely doing so with the expectation that your work output has a risk adjusted ability to create more reward than they’re paying you, otherwise they wouldn’t take that trade.