I have been buying guns over 40 years and I cannot recall prices ever "coming down".
Back in 1977, a friend of mine bought a base model Colt AR-15 for something between $500 - $700. I don't recall the exact amount, but I do recall I bought my first car for $500 at about the same time, and I remember his gun cost more.
Oly sells base model AR-15s for less than $600. Considering inflation and the improvements in machining, materials, and technology in general, I think you can get a better rifle now for less money in real dollars than in 1977. Also, I bought a NIB Springfield Milspec for a "sale price" of $410 circa 2002, and in 2004 saw the same gun in the same store selling for $390.
I do think most guns made now are about as inexpensive in real dollars as you're likely to see - we are essentially at the bottom of the cycle - and so will probably rise in price along with inflation and manufacturing costs. On top of that, you'll probably see an additional increase due to panic buying (sudden demand surge creating suddenly depleted supply).