You can't be serious ...
Without the Plebeian tribunate or any analogous institution, the Roman Republic wouldn't have been a democracy.
I.e., nothing to lose in the first place.
Just ask let say Polybios.
There were of course some relevant "
socio-economic issues"; in a nutshell, the Roman Republic was not a perfect society; no Utopia, no Heaven on Earth.
It was just by far effectively the most democratic state of this Planet at the time of its demise; exactly what let say Mr. Churchill and most modern political thinkers would have recommended for any society at any time. Just that.
BTW, please review the sources: Roman land had been carefully managed by the Senate and People of Rome for centuries; unsurprisingly, it had often been given to landless poor Romans.
What C Marius, LC Sulla, CJ Caesar, C Pompeius Magunus, M Antonius, C Octavius and some more chieftains were explicitly asking for was some public land (not theirs, of course

!!!) for their own partisan soldiers in their respective names.
All each one of them asked in return was the most absolute lavish loyalty of those soldiers.
I would love to be corrected here, but my impression has always been that there were still tons & tons of poor landless Romans even after the "
evil" Republic was duly displaced by the "
good" autocratic Empire (actually deliberately miscalled "
dictatorship" at the beginning).
And of course, our Isoruku and other posters are absolutely right here; to be fair, the
"Marian reforms" were just a part of a long process. However, ceding the absolute authority of your armed forces to any political adventurer with potentially unlimited ambitions has always been a terribly bad idea; just ask France 1799 or Germany 1933 ...
And aside of his fair tons of fans, of course good ol' CJ Caesar was largely to be blamed here; pretending in any way that he conquered the Imperial Roman Republic and that he was going to conquer anything else just in perpetual self-defense would be ... well, you already know what would that be ...
Last time I checked, there seems to still be some poor landless people all around this Planet, even within let say the US; some of them might even be or have been part of some army (again, let say of the US Army) ...
Here's the idea ... to solve the problem once and for all, just give me a legally enforceable life-or-death oath of absolute obedience from & over all of them (naturally surpassing their respective petty national loyalties).
Then, just call me Marius or Sulla (... well, you are just kind of already doing that

)
Or even better, just call me CJ Caesar Jr Jr Jr ...
How about that?