The Maryland State Roads Commission and its successor agency MDOT SHA have never cared about conflict between state highway numbers and Interstate highway numbers, because they (correctly, IMO) believe that the driving public can tell the difference. What they do/did object to was conflict between US highway designations and state highway designations; today, the only known duplicate numbers in the system today are US 219/MD 219 and US 222/MD 222, and the former is an unsigned segment of a so-far incomplete bypass of downtown Oakland in Garrett County.
Isn't MD-222 just a continuation of US-222, just like PA-222 is a continuation of US-222 at its other end?
No, the divided highway segment of MD 140 was never planned to be part of the Interstate system. The furthest north that a real freeway should/could reach is the intersection of MD 140 and MD 91, and doing that would require a LOT of right-of-way acquisition. Past that point, the existing project on the books to build grade separations at the major intersections between MD 27 and MD 97/Malcolm Road in downtown Westminster would substantially improve the capacity of the highway.
That Malcolm Road project was on the books as far back as 2011; I remember seeing it when I was looking up roads in Westminster shortly after I moved there. I doubt it will ever get built; Starbucks and Popeye's are both WAY too close to the road to allow for ramp construction, plus I *think* they built a new shopping center where the Ruby Tuesday used to be; they knocked down that building right before I moved out of Maryland.
Also right before I moved, SHA reconstructed the intersection of MD-140/MD-97 with North Center Street as the new mini-mall with the CVS was built replacing Len Stoler Chevrolet. This involved widening North Center Street and putting in dedicated turn lanes. Seems wasteful now to grade-separate that after that intersection was so recently expanded.
The layout of Gorsuch Road, both north of 140/97 going up the hill, and south of 140/97 with that rakish angle turn going behind the Domino's plaza, is such that I doubt any grade separation could be made there without creating a second intersection for the southern section of Gorsuch. I doubt the owners of the shopping plaza or the Hess/Marathon station would like THAT very much.
I think Ralph Street @ 140/97 got new signal heads and mast arms recently.
I think it's safe to say that MD SHA has abandoned any plans for grade-separating interchanges along the MD-140/MD-97 concurrency between Malcolm Road and MD-27.