In hockey, BGS was king for a long time and BGS 9.5 > PSA 10 in price. People who collect sports like baseball preferred PSA due to the set registry they have. Now that investor types are looking at key hockey RCs, who came from the other sports, they know PSA.
I used to agree with the bolded statement until I did a deep dive into PSA 10 vs BGS 9.5 datasets.
Hockey card collectors historically (pre-2020) sent more cards to BGS to get graded. This is fact.
BGS 9.5s did not outsell PSA 10s for a significant period of time. Look up any modern rookie.