Nah, I think there have been a narrative among some here on the forum that descent finishes in many cases are preferred over MTFs. In certain and few cases I agree. Mostly I prefer a MTF. There are really not very many locations well suited for descent finishes. I mentioned a few in Trentino, and there are some other in Italy. In France there are fewer options.
Anyway, I agree with you that the main problem is stage/route design. For the Giro we've sometimes seen really backloaded routes, like 2014, but the later years I think that a couple of the main problems have been too less use of the Apenninnes in the first 10-12 days, especially the norrthern part in Marche, Emilia Romagna and Toscana. In addition to far too many easy MTFs which in addition doesn't connect well to other climbs. Like Oropa, Pratonevoso, San Martino di Castrozza and Madonna di Campiglio.
In the Tour there have been too much focus on new and steep climbs, and not enough focus on good stage design. Although I like most of the new additons like Loze, Portet, Prat d'Alibs and Grand Colombier (Belles Filles is an exception, not to keen about that one) these should come in addition to better designed stages. Now they just come instead of, and dwarfing much of the other mountain stages.