Not weirdly. NASA wants new things - things that haven't been done before. I'm working a program now that had a development phase, a prototype phase, and now we're in the flight phase. If they'd come to us with a fixed-cost proposal for all that, we'd have replied with a no-bid. There's no way to bid it. Instead they gave us an NTE (not to exceed), which gives us latitude to experiment and figure it out.
@ScottSoCal @arstechnica which is fine for blue sky or high-technical-risk projects. There are elements of SLS which fit that description. The notion however of (say) the SRB component going over-budget is inexcusable. Itβs a well understood component (at least since Challenger). What needs to be cost+? SRBs should be basically equivalent to office stationary at this point. Order them for a fixed price. Same as buying additional flights on Crew Dragon.