This is wrong.
Initially Germany was charged with paying about 125 goldmark in total and first demands were to pay 20 billion until 1921. The Dawes plan then reduced it further to a economic viable option. Why? You forget that the German state of 1918 was essentially bankrupt and indebted beyond all belief because essentially germany believed the same the Allies believed: That the loser could pay the bills. Which in hindsight was nonsense.
In 1929 the Young plan postulated reparation payments that would amount to 110 billion until the 1980s. The Allies did not reduce things, they modified the way germany could pay this stuff.
Germany had no goldmark or foreign currency to give to the Allies that would hold up to a gold standard. The only way to aquire it was through exports (where else should it come from? The reichsmark was carried around in carriages to buy loaves of bread... okay a bit melodramatic here.)
The constant reshuffling and latter abandonment of the payment gives a glimpse how realistic the demands were. Germany got off better than it could have hoped for but only because it really wasn't that good off and the Great depression destroyed any hopes germany's economy could recover in a way that those reparations could be realistically paid. Germany of the 20s or 30s wasn't precisely well off economically. Even if its economy was still greater than France's this only demonstrates how
ed everyone was.
Case in point however, the French reparations taxed on a relatively unscathed country do not compare to a heavily indebted, bankrupt and instable nation after a long protracted war. 5 billion franc is way different than demands of 100-200 billion goldbacked currency (even the really paid ~24 billion). Germany did pay a similar amount within the first years, but the idea that a country could or would pay reparations openended for decades was surreal to begin with. The Allies didn't even know how much to demand up until ten years latter. It seems obvious to me that those reparations would have stopped one way or another before any of those ridiculous sums would have been paid.
Only effect it really had was to weaken the new german republic internally and externally by isolating them in the international field while they got flak from virtually everyone domestically.
It was really more than rightful retaking of German lands. The postwar order was simply a mess that created enough frictions between any of the newborn nations. That a now completely debased Austria and her former German lands elsewhere now looked to the Greater German solution could have been anticipated, given that Austria Hungary completely fell apart.
Wether anyone had any right to retake anything is secondary to the fact that the postwar order created plenty of ethnic friction.