We cannot expect unsaved people to come looking for a Christian to discover how to get to heaven. Sadly too many unsaved people never hear the Gospel message and face an eternity of torment and suffering, simply because the Christians around them refused to warn them to flee from the wrath to come. Not only is it ethical, but it is what believers in Christ are expected to do. Too many Christians sit back and hope someone will ask them how to have eternal life. They ignore the Holy Spirit's prompting to reach out to those who are perishing and snatch them from the flames, as it says in the Book of Jude. Anyone who follows the teachings of Christ should know that He clearly states that He is the ONLY way to get to heaven, and Scriptures clearly speak of the fate of those who do not receive the gift of eternal life offered freely through repentance and faith in Christ. The most loving thing anybody can do for someone else who is in danger, is to warn them of their predicament.
Evangelism is the product of the belief that everyone must embrace the exact same God and belief systems as a group of conservative Christians in order to go to Heaven. Those who refuse to accept God are warned of a fate worse than anything they can imagine. Telling people that they must accept your beliefs and then threatening them with a terrible fate if they do not in order to frighten them into accepting those beliefs unquestionably is not spreading faith, hope and love. It is tyranny.
There are sincere preachers, priests and ministers for whom evangelism is truly spreading the word of God and trying to reach and convert others to their respective faiths. Modern "evangelism" and televangelism seems to result in the creation of mega-churches: commercial religious empires - books, tv, podcasts, music etc. They seem to be less about true faith and more about true funds.