Visible doesn't always mean visible.
When I speak about the "visible church," I'm using "visible" to broadly say that the church is "accessible to sense perception."
Which means that the people of God can be seen. That the flesh of Christ is eaten. The blood of Christ drunk. We can hear the word of God preached, hear the word of forgiveness, and speak that word.
Of course, as Luther spoke well (especially in his Lectures on Galatians the church is "hidden." I know that among the people of God I see are hypocrites and false believers. I know that the body of Christ is hidden under the bread. That the blood is hidden under the wine.
And faith is always required to know the reality of the church. We don't confess that we "see" the church, we confess that we "believe in one, holy, catholic, and apostolic church." Because while the church isn't invisible, it's also not something that we can know without faith. Because ultimately, like all doctrine, it's revealed to us. It's like there's a curtain hiding the reality, and God pulls the curtain back. Matthew 16.17: "And Jesus answered and said unto him, Blessed art thou, Simon Bar jona: for flesh and blood hath not revealed it unto thee, but my Father which is in heaven."
Trying to make the church invisible only splits the one church into 2, one invisible, which we try to view as perfect, without sinners, without schisms, without faults, and the average, every Sunday get-together which we call church, but imagine it isn't, where there are preachers who occasionally do bad sermons, annoying Sunday school teachers, people who teach false doctrine, and sinners.
But the church is one. One church. God shows us some of it, and the rest remains hidden. But still there. And like all faith, it's a gift. Rejoice in that gift, and rejoice in the reality of the one church God has given to us.