If your church has changed to become more relevant, chances are, before the change was complete, it had already become irrelevant.
The Gospel is relevant; the Bible is relevant; Old Truth is relevant; Preaching is relevant. Those things never change because God never changes.
But the world changes. And just the time your new culturally relevant gimmick becomes popular, some newly styled gimmick will come up and surpass yours before the shine is off and your gimmick will be irrelevant.
I charge thee in the sight of God, and of Christ Jesus, who shall judge the quick and the dead, and by his appearing and his kingdom; preach the word; be instant in season, out of season; reprove, rebuke, exhort, with all longsuffering and teaching. For the time will come when they will not endure the sound doctrine; but, having itching ears, will heap to themselves teachers after their own lusts; and will turn away their ears from the truth, and turn aside unto fables. But be thou sober in all things, suffer hardship, do the work of an evangelist, fulfill thy ministry.
1 Timothy 2:1-5