that is a given, IR rules stipulate compulsory fencing if you are wishing to operate at even 160, let alone 200. At 200 they'll press for elimination of all at-grade crossing and replace them by ROB/RUB.
But those are fixed costs, irrespective of whether we go for talgo or make LHB high speed or bullet. I was concerned with the things which are variable.
In fact, talking about costs there are further issues too: tensioning of OHE to support speed of 150, improving cant deficiency at 150+ speeds to less than 100 mm...
more... (in WCR/WR tracks it is around 125 mm currently) and others. the investments are there, only lesser with talgo than with LHB