Being older is a terrible idea for so many reasons,but the main reason is because DCs son of superman experiment was a great success.jon has been a perfect example of how you create a pre teen character who is a hero.qe dont see that like ever,and when he was liked as much as he was it is not bright to take that way.
This isnt exactly something I personally want either,SB is coming back and this blurs lines between the boys more than before.sure they might act and look different,and yeah their powers are different(Jon has kryptonian powers with no limits,and SB has post crisis Byrne teenage level kryptonian powers with TTK),but the comparisons will be thrown around,and its not good for either of them.
I hope this is a very very short lived storyline thing,that will be gone soon,and we get back the younger and more original Jon back soon