In general, circular plots are made by "designers" to have data look cool but they're not what someone actually trying to use the data would choose. I will actively caveat that for things like antenna radiation patterns, they are the natural choice.
But for data that has no relation to circles, it merely confuses the reading of the plot. It is very difficult to make a numeric judgement of a data point where both the radius and angle are changing.
Quoting Tufte probably, they lead to confusion between the areal depiction and the linear relationship of the numbers.
Pie charts, spider diagrams, fitness / health monitor circles, energy usage in your utility bill shown as circles, these plots, etc., they're mostly a graphical gimmick.
That said, the data is really interesting.
I think for data which is circular in nature (in this case, as the Earth goes around the Sun), it makes sense.
Yes, a linear presentation works too. For me, that would be harder to read.