It impacts the buyer experience.
These two statements have a very different impact:
1. I love product X and I won't get paid if you buy it too.
2. I love product X and I will get paid if you buy it too.
Money motivates people to claim they love a product or that a product is good, even if not true. It's a problem that has plagued the internet for decades.
I don't think it's this binary.
Influence and power are far more intoxicating currencies than affiliate revenue.
And if someone complained "you're just publishing this helpful thing to become more influential in [community]," well, at some point we need to acknowledge incentives drive all behavior in one way or another.
Refusing the incentive doesn't make one per se virtuous.