Corinthians 1:9: "Or do you not know that wrongdoers will not inherit the kingdom of God? Do not be deceived: Neither the sexually immoral nor idolaters nor adulterers nor men who have sex with men nor thieves nor the greedy nor drunkards nor slanderers nor swindlers will inherit the kingdom of God. "
There's Paul in the NT, clearly telling the church at Corinth that homosexuals will not be saved. Yet you say the prohibition against sodomy doesn't apply to Christians (one of the most incredible claims I have EVER seen online).
God's moral law doesn't change.
You appear to be reading comprehension challenged.
Try reading your own quotation: “Do not be deceived: Neither the sexually immoral nor idolaters nor adulterers nor men who have sex with men nor thieves nor the greedy nor drunkards nor slanderers nor swindlers will inherit the kingdom of God.”
Nine sins are listed. The fourth on the list is homosex, which certainly does not imply any uniquely or specially sinful status.
Homosex is against the law of God, as stated in this scripture and others. But then so is adultery and sexual immorality in general. Which means any sexual activity outside of marriage.
This is a higher standard, not a lower one.
In practical terms, most “Christian” churches today, even the most conservative ones, accept heterosex before marriage. Certainly they do not denounce it with the fervor they reserve for homosex. Yet in the scripture above there is no particularly obvious reason why B should be considered more sinful than A.