nprofile1qy2hwumn8ghj7un9d3shjtnddaehgu3wwp6kyqpqehte0gdeplg97pucet2au4q386qtwzx3w5075h6ww2y8kvre5w0qfgh68j (nprofile…h68j) you can probably get to ~140 with only few local drops (think old+new westbahn), that's slower than 200 (and the route is not 25 but 35km), but neither is an actual hsr anyway and not worth such a massive investment
fitting 4 tracks in the valley is then only a problem if you are not willing to do any redevelopment, but that's intellectually completely bankrupt, if you don't do it, there is no point in the new line, keep 20m peak regional frequency, just buy bigger trains, that will be perfectly enough, and you're left with enough capacity to handle ic and freight with occasional optimization and better passing loops, if you are going to redevelop to actually densify the built-up areas around the line, well, guess what