it‘s not flat the suspension is good.
Bent rim or bad shocks. Could also be tire separation internally.
It all depends how much money you want to put out. Air shocks are good but shackles are cheaper. IF you have leaf springs in the front you could add one.
I have read a lot about this and from what I understand it has a lot to do with the tire design and riding style. Everywhere I have read about this says it's basically normal. If you go online I think the august edition of one of the motorcycle magazines had a big article about it. I think it was Cycle World ??
Tire pressure, riding style. Believe it or not unless there is a recall 99% of the time a front tire that requires 36 psi that has been ridden for 1000 miles on a psi of 30 or lower, the wear bars will show.
Look for springs rated for a big block and you should be set.