I’m inclined to agree with you about some kind of leftist government, though I do know that the monarchists like Denikin etc. were also strong AND they had the army on their side, so a cabal like post-Imperial China
The Imperial Russian Army was corrupt as heck, morale was very low and they were both worn down and war weary by 1917 - having basically been at constant war since *1904*. The Army being on the monarchists’ side was far less of a benefit than it would sound.