Doesn’t seem that way. If anything, it favors new players level 1-100 and harms the level 100-1000 players that just want to open up Explore 12 without having to live at Explore 12 for the rest of their lives.
Now they’re half obligated not to go up in Explore until they get this mythic (unless they don’t know this is a thing).
Always level 150 seems kinda poorly thought out when rewards are scaled to the last earned Boss Chest. Why would interrupting the flow of gameplay be a good thing?