Are you being compelled by a curse inflicted upon you by an evil fairy godmother that prevents you form using material from another publisher?

So you feel that Eberron was too different from standard DnD to remain the default setting
Yes. Well not burned, but ripped up and thrown away.Did someone burn all your copies of Dark Sun, Al-Qadim, Oriental Adventures, Dragonlance, Eberron, Planescape and Spelljammer? If they did, you can still get them cheaply at the DMs Guild site and use them easily in 5E.
This is why it's their default world. It's the most fleshed out world with the most characters, the most stories, and any of the campaigns from most of the other settings can easily be converted. Unfortunately for settings like Dragonlance and Dark Sun, after the main campaign, the setting pretty much just dies.The same can be said for FR which has more pre 5E material than all of those settings combined. So why do we need more?
As for Forgotten Realms, I think parts of it do have a distinct 'Canadian Wilderness' frontier feel

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.