The monarchy was not "overthrown" by the provisional government; the latter was formed after the former abdicated, and was dominated by pre-existing noble elites.The Bolsheviks didn't overthrow the monarchy. The monarchy was actually overthrown by the provisional government. The Bolsheviks, at the time merely the leading party of a nominally democratic Petrograd Soviet, staged a military coup against the provisional government (itself lead by the Socialist Revolutionary Party). The Bolsheviks then began the increasingly brutal suppression of other socialist parties, nominally under the excuse of preserving the peace with the Central Powers which many other socialist parties opposed.
By the "overthrow of the monarchy", I'm not merely talking about the abdication and formal transfer of power to another broadly conservative provisional government. I'm talking about the defeat of the White Army (with its heavy Tsarist presence), the storming of the Winter Palace (with its heavy Tsarist symbolism), and the killing of the imperial family. That-- and successfully forming a government-- is what revolutionaries worldwide remembered.
Uhrm, what about them? None of these would have been more successful with the Russian Republic still in place.That's not even close to a complete list. What about the revolution in Finland, crushed by the whites and their German allies after the Bolsheviks ordered the people in occupied territories not to attack the forces of the Central Powers. What about the Ukraine, crushed by the Bolsheviks themselves. Catalonia, crushed by Stalinists. The third revolution in Russia itself. The Krondstadt rebellion, also in Russia itself.
Only Germany and Hungary, both of which took place once the Civil War was well underway, and both of which explicitly took inspiration from the success of the Russian socialists in forming a government.Several of the ones you describe had already happened by the end of the Russian civil war.