The existence of a single party doesn't mean the lack of opposition, it means that the struggle between opposing lines is carried out within the party. The number of political parties wasn't the issue, and things wouldn't have been better if it were easier for counter-revolutionaries to organize.
That's a delusional belief Single party states are rife with corruption. onece the party's leadership is corrupt they will do whatever it takes to maintain That corruption any real attempt to perform the party will be met with retaliation
If the problem was corruption, then that's a different conversation than the number of de jure political parties. Corruption is a problem for whichever entity holds power, whether in a single party, two party, or multi-party arrangement. It's a metter of the particulars of the party not their number
Ehhhh.. multi-party states aren't particularly better at fighting corruption, the best thing for fighting corruption is a professional civil service. And single party states still fight corruption quite well. China has certainly gotten theirs under better control.