Because it's mostly distressed lending, the preference is almost entirely on the lender not the borrower. IMF loans are required to be fairly transparent, while B&RI have so far been opaque (not clear what the terms, payment priority, or valuation of projects as collateral). The IMF won't even lend to countries where the lending would be used to pay off other creditors (since that's a transfer between creditors). It's unclear what China's response will be if the projects they claim are then nationalized (dams, ports and railroads are likely to be considered national infrastructure). Decisions to accept loans aren't made by the population that will pay and when governments change so do priorities.
Since there's already a China debt problem (and ROI problem) though, it's more likely the loans just dry up. That already started in 2017 (see graph in article).