The standard is to bold the best figure per column. If none are significantly different you don't bold any generally but it's standard practice to use this to highlight which approach is best in each task.
I think colouring a column is the common approach to drawing attention to your own while still respecting the best is bold custom, which they've sort of done with the header, but personally I'd have gone with the cell background for the column.
The table just below this shows the other models doing better on half of the benchmarks; the Replit column being in boldface is misleading.