From Mr. Guaidó's point of view, humanitarian assistance cannot be politicized. Humanitarian assistance is humanitarian assistance, period, so it shouldn't be politicized whatsoever.
The Maduro regime was responsible for politicizing the delivery of aid. It sought out the involvement or contribution of other institutions in China and Russia in exchange for goodwill in relation to humanitarian aid. That is what you call politicizing.
For Mr. Guaidó, however, there is no politicization, as the top U.S. sites indicate. Those statements are unequivocal about the humanitarian crisis in Venezuela, as supported by the statistics I provided earlier.