ここの「戻るだろう」は次のような言い方ができます。
... will go back to ...
... will return to ...
例:
I think the price of airplane tickets will go back to where they were before COVID sooner or later.
「そのうち航空券の値段はコロナ前に戻るだろう」
... will go back to where they were before COVID で「…はコロナ前に戻るだろう」と言えます。
ご参考まで!