“polarimetric” in this case means that all four polarization channels are required: HH+HV+VH+VV
But Sentinel-1 is dual-pol only (VV+VH). There is a dual-pol decomposition in the dropdown menu, but some decompostitions or polarimetric operators will not work with Sentinel-1 data.
Please have a look at this post, where we discussed what is possible with Sentinel-1 and to what extent it makes sense: H-Alpha Plane Problems