Uber Said to Raise $1.6 Billion in Convertible Debt to Expand 12 years ago
Traditionally, debt has no upside
Not really--if interest rates decline (either in the overall economy or if a bond's issuer is seen as becoming less risky), the value of a bond will go up. The 10 Year US Treasury bond increased by over 10% last year, for example.
Also I agree with you about ending the deductibility of interest (for other reasons as well), but I'm not sure why you say the distinction between debt and equity is diminishing--convertible debt has been around for a long time.