No, for many people with disabilities, the title levels are a prerequisite to smoothly navigate a page. If you want to do one thing to improve your accessibility, this is probably the simplest and most important one.
Each page should have a title, which in many cases is also Heading 1 (H1). The next heading on the page should have Heading level 2 (H2). If there are more headings within that "chapter", they get Heading 3 (H3) etc. In this way, for example, a visually impaired person can quickly have all H2s read aloud and then choose where to click to listen to more content.