The V250s are all now being transported back to Italy. The HSL in NL is currently carrying Thalys trains plus a LHCS 'Intercity Direct' service hauled by a small pool of Traxx locomotives, most of which NS has bought, new since the V250 fiasco. They are, I believe, limited to 200kph but this is no great problem given that the HSL line is very underused. Essentially, as others have indicated, NS does not have the resources to order any new fast trains for the line nor is there any particular pressure to. The Benelux trains to Brussels via the classic line are more or less back again so connectivity with BE is restored. The Thalys trains can get very full/expensive because they are so much faster but for most journeys the Benelux service is just fine.
What you have to realise when reading through these posts is that politics in NL can get very viscious, with many MPs having it in for NS management for numerous problems over the years occasionally justified but mostly not. Actually, NS runs one of the best services in Europe IMHO and deserves much more support by from its customers and Ministry that it seems to get!