If you believe in Jesus with all your heart, and live through Him toward others, you are truly a disciple of Christ. Yet, religion does matter.
After all, Truth does matter!
Truly, you can't say, 'I have Jesus, and I don't need anything else.' Or 'I have Sacred Scripture, what else is there?' This is equivalent to a blind man driving a massive truck on a busy highway. The task is too big for him alone! He needs to see what he thinks he perceives. He needs to understand what is behind him, concurrent with him, and in front of him.
But without vision how can he?
The Catholic Church, in her Apostolic Tradition, is the visual guide for the blind, giving sight in the Real Presence of Jesus in the Eucharist, in all seven sacraments, and in the (all too human) apostolic hierarchy, guided by the Perfect Love of the Holy Spirit.
"Tend the flock of God in your midst, overseeing not by constraint but willingly, as God would have it, not for shameful profit but eagerly. Do not lord it over those assigned to you, but be examples to the flock." 1 Peter 5:1-4
What non-Catholics get wrong about Catholicism is what they think the Catholic Church is all about. Many a non-Catholic thinks that the Catholic Church is a Pope and Bishops making up doctrine as they go, ordering sheepish little Catholic's around, practicing magic, and teaching human superstitions.
Their view of the Catholic Church is upside down and inside out.
Catholicism starts with the Real Presence of Jesus, in the Eucharist, and flows through seven sacraments--into the world--as a font of Mercy. The Pope, Bishops, and priests, are but a (vital and necessary) means for this font of heavenly grace. The 'source and summit' of Catholicism, therefore, is not a group of men, but Jesus Himself in Sacrament, Word, and Spirit.
"You spread the table before me in the sight of my foes; You anoint my head with oil; my cup overflows." Psalm 23:1-6
I suppose a few Catholics, here and there, are guilty of idol worship. But that is not authentic Catholicism! Authentic Catholicism respects the Pope as the Vicar of Christ, but realizes Jesus as Christ! Authentic Catholicism venerates (deeply respects) Mary as Mother of God--and cum-redemptrix (with He who saves), but realizes Jesus as the sole Savior of the world! Authentic Catholicism follows the lead of the shepherd (the Bishop), but always remembers that Jesus alone is the Good Shepherd!
Authentic Catholics are authentically Catholic by believing, behaving, repenting, and forgiving as the Apostles of Christ teach. Jesus would have it no other Way!
"Simon Peter said in reply,
'You are the Christ, the Son of the living God.'
Jesus said to him in reply, 'Blessed are you, Simon son of Jonah.
For flesh and blood has not revealed this to you, but my heavenly Father.
And so I say to you, you are Peter,
and upon this rock I will build my Church,
and the gates of the netherworld shall not prevail against it.
I will give you the keys to the Kingdom of heaven.
Whatever you bind on earth shall be bound in heaven;
and whatever you loose on earth shall be loosed in heaven.'" Matthew 16:13-19
The Scriptures reveal it.
The Catholic Church, as held in practice since her inception at the foot of the Cross, in the Blood and Water which flowed from Jesus' side, lives, and teaches it.
Peter was the Rock on which Jesus built His Church. And every successor of Peter, all men as faulty as Simon Peter was, is endowed with Jesus' promise--in the Power of the Holy Spirit--to overcome the powers of 'the netherworld' and lead the pilgrim disciples, through Word and Sacrament, to the promised land in eternal life in the Father, Son, and Holy Spirit.
You are free to believe or disbelieve.
But, carefully, you'd better pray, research some history, and check your personal prejudices against the Truth.
After all, obeying our Loving Savior is an important matter.