That's a bug, not a feature, imo. I believe we're already the youngest team in the league and we'll be even younger the minute we trade Simmonds, and we already have A LOT of young talent in the system to work into the mix. Tolvanen or a similar prospect would have to duke it out with all of the other young guys for limited roster spots in mostly bottom six roles--there's only so much playing time to go around.
Meanwhile, a late 1st in a strong 2020 draft would be an asset that matures down the line when some of the younger guys on the team now are fully grown into vets. It's also an asset we could use to better the team via trade.
That said, I'd easily rather Tolvanen than a late 2nd round pick as the return, if that's what the other option is going to be.