Largest contentful paint is one big gatsby-background-image and very slow

Question

For those stumbling on this question wondering how to improve their lighthouse score in general, I posted an answer on this topic on another question with lots of general tips.

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I'm running PageSpeed insights and my biggest problem is the largest contentful paint, at about 8-10 seconds. Below they list my largest contentful paint element

Largest Contentful Paint element 1 element found
This is the largest contentful element painted within the viewport. Learn More
Element

This is the a paragraph that appears above here    
<section class="mainBgImage gbi--716926567-eDXcajFRMpQ2F1s7wNgLk1" style="background-position:center top;background-repeat:no-repeat;background-size:cover;position:relative;opacity:0.99" role="img">

This element is an image that spans my whole website in the background. It was originally a 1.2 MB png that i load using ...GatsbyImageSharpFluid_withWebp_noBase64 with a maxWidth of 1950.

This is the code for how I render it

    import BackgroundImage from 'gatsby-background-image';

    ...

      <BackgroundImage
        Tag="section"
        role="img"
        className='mainBgImage'
        fadeIn={false}
        // style={{objectFit: 'contain',  width: '100%' }}
        style={{
          opacity: 0.03,
          backgroundPosition: "center top",
          
        }}
        fluid={wheatImgProps}
      >
          {children}
      </BackgroundImage>

And this is the static graphql query

    const data = useStaticQuery(graphql
        `query LayoutQuery {
          wheatImg: file(
            extension: {regex: "/(jpg)|(jpeg)|(png)/"},
            name: {eq: "wheat-background"}
          ) {
            childImageSharp {
              fluid(maxWidth: 1950) {
                ...GatsbyImageSharpFluid_withWebp_noBase64
              }
            }
          }
        }
        `
      )