Not to mention that in practical terms, the Jizya would often end up being double the Zakaat and that tax season was often a horrible nightmare for the Dhimmis.
As S. D. Goitein says:
"It was, of course, evident that the tax represented a discrimination and was intended, according to the Koran's own words, to emphasize the inferior status of the non-believers. It seemed, however, that from the economic point of view, it did not constitute a heavy imposition, since it was on a sliding scale, approximately one, two, and four dinars, and thus adjusted to the financial capacity of the taxpayer. This impression proved to be entirely fallacious, for it did not take into consideration the immense extent of poverty and privation experienced by the masses, and in particular their way of living from hand to mouth, their persistent lack of cash, which turned the "season of the tax" into one of horror, dread, and misery. The provisions of ancient Islamic law which exempted the indigent, the invalids and the old, were no longer observed in the Geniza period and had been discarded by the Shāfi‘ī School of Law, which prevailed in Egypt, also in theory."
But more than all of that, this is clearly discrimination. A Muslim and a non-Muslim are clearly not equal in a theocratic Muslim state. Which is why such a state is inherently unjust and will eventually fall.
Speaking about the Shafi madhab:
THE NON-MUSLIM POLL TAX
o11.4 The minimum non-Muslim poll tax is one dinar (n: 4.235 grams of gold) per person (A: per year).
The maximum is whatever both sides agree upon. It is collected with leniency and politeness, as are all
debts, and is not levied on women, children, or the insane.
o11.5 Such non-Muslim subjects are obliged to comply with Islamic rules that pertain to the safety and
indemnity of life, reputation, and property. In addition, they:
(1) are penalized for committing adultery or theft, thought not for drunkenness;
(2) are distinguished from Muslims in dress, wearing a wide cloth belt (zunnar);
(3) are not greeted with "as-Salamu 'alaykum";
(4) must keep to the side of the street;
(5) may not build higher than or as high as the Muslims' buildings, though if they acquire a tall house,
it is not razed;
(6) are forbidden to openly display wine or pork, (A: to ring church bells or display crosses,) recite
the Torah or Evangel aloud, or make public display of their funerals and feastdays;
(7) and are forbidden to build new churches.
o11.6 They are forbidden to reside in the Hijaz, meaning the area and towns around Mecca, Medina, and
Yamama, for more than three days when the caliph allows them to enter there for something they need).
o11.7 A non-Muslim may not enter the Meccan Sacred Precinct (Haram) under any circumstances, or
enter any other mosque without permission (A: nor may Muslims enter churches without their permission).
o11.8 It is obligatory for the caliph (def: o25) to protect those of them who are in Muslim lands just as
he would Muslims, and to seek the release of those of them who are captured.
o11.9 If non-Muslim subjects of the Islamic state refuse to conform to the rules of Islam, or to pay the
non-Muslim poll tax, then their agreement with the state has been violated (dis: o11.11) (A: though if
only one of them disobeys, it concerns him alone).
o11.10 The agreement is also violated (A: with respect to the offender alone) if the state has stipulated
that any of the following things break it, and one of the subjects does so anyway, though if the state has
not stipulated that these break the agreement, then they do not; namely, if one of the subject people:
(1) commits adultery with a Muslim woman or marries her;
(2) conceals spies of hostile forces;
(3) leads a Muslim away from Islam;
(4) kills a Muslim;
(5) or mentions something impermissible about Allah, the Prophet (Allah bless him and give him
peace), or Islam.
o11.11 When a subject's agreement with the state has been violated, the caliph chooses between the four
alternatives mentioned above in connection with prisoners of war (o9.14).
Source: Reliance of Traveller by Al-Misri
Topic: Fight those who do not believe in Allah!