Unfortunately no. :(
WikiTree uses the same software (albeit an older version) as Wikipedia. I'm sure the developers have a little bit of control over the width of the display, but ultimately, the profile pages force the display of the right column so that the bio sections display content that is too large just like you see on your page.
I'm just glad that the profile pages don't have two side bars like WIkipedia, only one! Otherwise, we'd have even less space.
BTW, you can update the tags on your question to get better attention or feedback by adding: bugs, improvements, style, wiki_markup. Just examples, but general is better than more specific.