Yes, one of the reasons for the looming pilot shortage is the 1500 hour rule but before blaming the FAA, you need to understand that it was mandated by Congress. The FAA had no choice but to comply. Even so,when military pilots can go 121 with 750 hours and graduates of an aviation program with a BS degree can do so with just 1000 hours; the 1500 hour floor is really less of a factor than many think it is.
As a side note, I personally do not know if the ability or knowledge of a pilot with a BS degree is far superior to that of one without a BS degree but I really doubt it. I have no idea how that came about.
A bigger issue is there are less new pilots entering the pool than ever before. Less pilots overall mean less hitting the magical number of 1500 or 1000 or 750. And when you consider many potential airline pilots (except for the prior military ones) build their hours instructing, well the problem is compounded. After all if there are less students to instruct then it becomes harder to build hours by instructing alone.
To be honest, I like the idea of having a higher standard to become an airline pilot. 250 hours and just a CPL to fly a sophisticated jet aircraft carrying a bunch of people is far too low of an experience level in my opinion. I do think however that 1500 hours to be in the right seat might be too restrictive.
One possible option that I like is lowering the minimum to 750 - 1000 hours but still requiring an ATP written and checkride for the right seat while leaving the 1500 hour ATP for the left seat.
One thing for certain, this issue will not be resolved anytime soon as changing it at this point would require congress to do something.