Please find me one pre draft opinion where Matthews is being heralded as mcdavids equal, a generational talent, or the best prospect in years.
It takes about 1 minute of Google search to find multiple scouts and quotes from anonymous executives claiming Bedard as such. Notice how it's never "best prospect since Matthews" and always the best since McDavid, that's because he's unanimously seen as the better prospect than Matthews was.
Maybe you viewed Matthews higher than most, and maybe you will be right about who will be the better NHL player because there are no guarantees bedard tops what Matthews has done, but as it stands in the scouting community bedard is regarded as far and away the better prospect at this point than Matthews was.
Matthews was getting kopitar comparisons and Bedard is being held to the Crosby/McDavid standard, whether you like it or not.
I personally thought MacKinnon was a far Superior prospect to Eichel for instance, but I'm not naive enough to think many people didn't agree with me, and despite MacKinnon clearly becoming the better player and somewhat validating my opinion, I don't necessarily believe MacKinnon would have been drafted ahead of Eichel had they been in the same draft, because I realize most people didn't agree with that take at the time