I think miles are more valuable now than ever. In the past if you were flying a route with lots of competition then most times I'd buy a ticket rather than burn miles as many popular routes, even transcon could be had for $250 or less. Save miles for international or domestic underserved routes.

But today everything is through the roof, and fares will get worse as flights are cut.

If you think airlines will go out of business before you use your miles then go to CC and exchange for hotel gift cards or similar.