I'd say that since today, modern western government spending floats around 50% of the total, and that's widely believed roughly the average tax rate of feudal times (with big variance by place and time), they're about the same proportion wise.

The difference of course being, in our wealthy age, the communal benefits nowadays are similarly greater.

I think certain comparisons regarding social spending now are just cultural self-congratulation.

For instance, yes a politician can't just pocket any takings directly. Instead, it has to be indirect - post-office speaking fees, consulting, etc, that can easily render them far richer than any manor lord of old.

Also in such undeveloped, poor, and violent times, the value of law, military power, as well as what communal spending did happen - a granary, a road, a temple - would have similar value parity to them then as to us for what we get in the modern era.