We are not required to believe in Jesus Christ anymore once we become members. You may not be able to secure a temple recommend, but if you do not believe in Jesus anymore, the home teachers and missionaries will still be sent to try and work to reclaim you.
However, if you wholly believe in Christ but are not convinced of His present guidance, empowerment or involvement with the church's human leadership–whether it is due to a lack of evidence of their proclaimed spiritual gifts, or due to them make doctrinal and policy changes which contradict, deny or set at naught the gospel of Jesus Christ–then you will probably be excommunicated, and likely ASAP.
To contrast, in Joseph's day, if he were to learn of someone who truly believed in Christ but was yet unconvinced of his divine gifts or calling as a prophet, I think that rather than excommunicate or ostracize them, Joseph would have invited them to come hear him prophesy and determine for themselves whether the words he spoke were of God or of himself. Even then, if they remained unconvinced of Joseph, he would still be happy to welcome the fellow believer in Christ among the ranks of his congregation, believing a true seeker of Christ will always be led to the truth. I think Joseph amply demonstrated that he respected the supremacy of the Supreme, the inconsequence of himself in comparison, and the agency of man in their choice of beliefs.
Because Christ is now of definitively less consequence than the Brethren to a person's membership in the Church, it necessarily takes his name in vain to place it in the Church's title as though the Church is His. I think the leadership has unwittingly confessed this to a degree, as the Church is legally a subsidiary trademark--a lesser subdivision--of The Corporation of the President of the Church of Jesus Christ of Latter-Day Saints. It is the President who is supreme, he is the literal owner of the Church rather than Christ, with Jesus Christ serving only as the namesake of what the President owns.
Therefore, to alleviate taking the Lord's name in vain, I submit that the Church should officially change its name to "The Church of [Insert Senior Apostle] of Latter-Day Saints."
That should fix things.
