Roosevelt antagonized Morgan when he stopped Morgan’s big Northern Securities merger. Later on, Morgan partners backed TR’s 1912 run for the presidency. Teddy had a reputation as a “trustbuster,” but he grew more friendly to big banking and megamergers after leaving office. It’s not clear that TR’s family had been financially involved with Morgan in his formative years though. There were plenty of old money New Yorkers who weren’t.
The 14th Amendment was orginally intended to deal with the aftermath of emancipation and efforts to disenfranchise freed slaves. Corporations used the amendment after courts said it applied to corporate “persons,” but I doubt that was the original intent of the amendment.