The reputation received from a vote is independent of the Steem price, as the ratio of rshares to Steem power is independent of the Steem price. An account with a Steem power of 1000 SP has a vote of 40572847921 rshares, no matter if the Steem price is 0.1$ or 2 $.
Thus, a vote influences the reputation independent of the current Steem price.
What you said is true, but as soon as you try to convert to “SBD” it starts to include the price in the calculation.