Are Innovations Major Sins?

Allah's (ﷻ) saying: {Verily, Allah does not forgive Shirk (disbelief / associating partners with Allah), but He forgives anything else for whom He wills.} [An-Nisāʾ (4):48] And the meaning is that bidʿah (innovation within religion) is greater than major sins because it is a form of criticism to Islam, (it is) an innovation in the (religion of) Islam, and it is accusing Islam of deficiency. For this (reason), (a person) innovates and adds (to the religion). As for disobedience, it is following desires and obedience to Shaytan. It is less severe than innovation. And the sinner might repent, hasten (to repentance), and learn his lesson. As for the innovator, he sees himself to be correct, so he does not repent. He sees himself to be correct and that he is striving to do good. Therefore, he persists in innovation. We seek refuge with Allah! And he sees the religion to be deficient, and that it is in need of his innovation. Due to this, the matter of innovation becomes more severe and dangerous than disobedience. Allah says regarding the people of disobedience: {But He forgives anything else (i.e., other than Shirk) for whom He wills.} [An-Nisāʾ (4):48] Sinners are under the Will of Allah. As for the people of innovation, their evil is great and very dangerous because their innovation implies criticizing Islam, and that it needs this innovation. Also, the one committing the innovation sees himself to be right. Hence, he persists upon it, and argues for it. We ask Allah for wellbeing.