Majority of WW2 Toks were made by mal nurished workers like women and children. That's why quality of ww2 made pistols may vary. Finish is rough and fitment of parts can be better made. It is well known fact that during combat, officer armed with TT 33 was expected to live 15 min, if he is lucky. During this 15 min of actual fighting 16 rounds of ammo was considered enough for tt 33 armed solgier to either accomplish his objective or be killed with pistol being damaged by explosion, being lost in the trench or being destroyed. Thus the war finish firearms are made as fast as possible and as cheap as possible in order to meet attrition rate. If pistol survived the deployment and fired more than 16 rounds (2 mags) it was considered as bonus.
Post war toks are built with less demand and pressure, with much finer attention to detail. Things that were considered acceptable during ww2 were not accepted during late 40s and early 50s production. That's why early 50s izhevsk toks are made to finer tollerances.
After 1951 tooling for pistols were sold to China and Makarov PM was adopted as standard side arm. However TT33 was never phased out of service, and even untill now Toks being used in Russia with remote areas police forces and other agencies where less urban deployment is likely and powerful pistol round is needed.