How can a Muslim deal with someone who abandons the constants of the religion and describes the committed as extremist? And has Islam become so in line with reality that some preachers avoid speaking the truth for fear of alienating new converts to Islam?

Necessity means that a person reaches a point where they would perish or be close to perishing if they do not consume what is forbidden. Its definition is for the people of ijtihad (independent juristic reasoning). A Muslim must subject reality to Sharia, and keeping pace with the times does not mean violating God's rulings. Considering the situation of new converts to Islam and gradually dealing with them is wise, just as the Prophet, peace and blessings be upon him, did not demolish the Kaaba out of consideration for his people who were new to Islam after the Jahiliyyah (pre-Islamic era), and that was to win over hearts and avoid alienating them, unless it involved abandoning a Sharia command. Residence in Western countries is forbidden except out of necessity.