More tape on one blade than another might unbalance it… air resistance increase from the texture of blue tape could also be an issue.
Another way to increase contrast would be to change the ceiling color above the fan. This could be done with something temporary if one is careful that it can’t fall into the fan, or painted.
Wouldn’t tape disbalance the fan so that it breaks faster / starts to make sound after a few months? Not sure, but these problems seem plausible.
More tape on one blade than another might unbalance it… air resistance increase from the texture of blue tape could also be an issue.
Another way to increase contrast would be to change the ceiling color above the fan. This could be done with something temporary if one is careful that it can’t fall into the fan, or painted.