Can ResearchGate upload preprints from ArXiv without author's consent?
Yes, anyone can share your work as long as they follow these restrictions.
That is the nature of an open license. You have already explicitly consented to let them do that.
The actual licence clause that matters here:

For purposes of this Public License, the exchange of the Licensed Material for other material subject to Copyright and Similar Rights by digital file-sharing or similar means is NonCommercial provided there is no payment of monetary compensation in connection with the exchange.

To answer the (very relevant) question that got buried in the comments:

If I want the preprint to appear only on arXiv and restrict platforms like ResearchGate distributing it, what license can I use?

There is a licence that you can choose which leaves you with full control over the use and copyright: arXiv.org perpetual, non-exclusive license. There is no legal right for anyone to rehost a manuscript that you give to arXiv under these terms. The only thing it allows is arXiv (and nobody else) to host your manuscript. Nobody else can use or reshare it for any (non-fair use) reason.