Some people think all first round picks are equal. There's a huge difference between top 5 first round and late first round.
Same people don't understand the go for it window and the build window.
It's not like Leafs are trading their 1st pick every year. They didn't last year. Only one other year when they won the Canadian Division.
Once Matthews and Nylander contracts end and if one or both jump ship then they can build again with draft picks.
Winning a round would probably be considered a success. That's how low the bar is.
Certainly agree with your take on not all first rounders alike - a 15th pick is not even close to a 5th pick.... much less a 25-30th pick which is another below those two. Reminds me when people here argued that a late first the Leafs received in the Kaberle to Bosotn deal made up for one of the 2nd and 10th overall they ended up giving for Kessel. They were not even close to similar value.
Instead of windows, I go with the franchise success cycle concept - similar thoughts really - this is the time the Leafs have to move nnn critical assets for improvements that they believe are better than marginal.
In terms of the Leafs only trading away first rounders twice -- they also traded their 2022 1st for a 2nd (to clear cap). And they traded their 2019 1st to clear cap (getting rid of Marleau). So in the last 5 years they will only have had one first. Again, arguably worth the risk.