The site seems to be promising to later evaluate a rather large number of widely ranging predictions. If it manages to actually keep this commitment, it will make an important contribution. The five year limit on prediction horizons is unfortunate, but of course site authors have every right to limit their effort commitment. I do suggest that they post the date that each prediction was submitted, along with the date it was made, to help observers correct for selection effects.
The site seems to be promising to later evaluate a rather large number of widely ranging predictions. If it manages to actually keep this commitment, it will make an important contribution. The five year limit on prediction horizons is unfortunate, but of course site authors have every right to limit their effort commitment. I do suggest that they post the date that each prediction was submitted, along with the date it was made, to help observers correct for selection effects.