I assume by absolute deaths, you mean the plain count, the raw numbers. Absolute deaths also decreased under Biden. It's hard to tell from the chart, but it looks like the proportional drop from start/inauguration is about 1/8 under Biden and somewhere between 1/8 and 1/4 for Trump, so a larger proportional decrease under Biden. As for the ceasefire, I think it's more likely that's happening because global backlash is getting to be too much and risking their longterm political support as the younger generation grows older and starts getting into office, than it is for the same Trump who told them to finish the job suddenly grew a conscious and made it his personal priority to halt the genocide.
That said, I'll try to look into issues with the chart before I bring it up to anyone else.