The Church universal has never had universal agreement on the canon of scripture, and it hasn’t limited the Spirit’s ability to guide the Church. Under your argument here, there are numerous fathers of the Church who were not guided by the Spirit, Athanasius notable among them. There were numerous individuals and patriarchates who held to different canons long before the Reformation era.
If true this would be a problem for any group that practices any form of Sola Scriptura. How can doctrine and practice be judged against Scripture if there is not authoritative canon?
Because each communion, including Catholic and Orthodox, make a determination about the canon, and how to use it.
The evidence suggests that they don’t. They all accept almost the same canon, with very slight differences, usually for liturgical purposes.
They can, and do, interpret - “use” - the NT thousands of different, often wildly contradictory ways. That part, yes, each communion does make their own determination. But the canon?
The mass of communions will accept slight differences (for instance, among the Eastern Churches) in canon, that are rarely significant in shaping doctrine. But if any Christian communion determines a canon much different from the template, like the Mormons, the great majority of communions reject their right to “make a determination about the canon”.
Because the great majority of communions follows the same template. (From where?)