If our salvation were to be contingent upon getting every jot and tittle just so then would one be lost if they disobeyed the Great commission? Technically the Greek there isn’t an imperative but over and over again we understand the Christian mission to be one of going and telling.
There is no more important directive in the Christian life than the call to evangelize the world and, sadly, none that are more easily passed over.
I believe part of this has to do with institutionalizing the church especially through reliance on hired staff. This move, taken to the extreme has made one’s contribution to ministry their literal monetary contribution with the understanding that that money goes into the work of the church. What is missed is that the work of church is the work of the church (aka the people).
So on one hand we press the priesthood of all believers, almost as an anti-Catholic apologetic, while ignoring the implications and application of what that actually means and requires.
What would happen if even 10% of the congregation were actively evangelizing the community? 20% 50% What would happen? For the most part, if we do what we were told to do the church functions in a healthy manner and healthy things tend to promote growth. There is little to no reason that Christianity should be in decline in the West other than that the church gave up on some of the most simple and straight forward things we were told to do.