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It's absolutely essential that your company website is fast.

Don't purchase slow, cheap web hosting, regardless of your business type.

Instead purchase super fast hosting for your business.

Sometimes, it's much more expensive, but it's well worth it as it can help improve your organic SEO.

We purchased lightning-fast hosting; this is the one reason why we are now selling more bath garden offices than ever before before.

it is important to distinguish between PageSpeed Insights and Lighthouse. Maybe it's more important to follow PageSpeed Insights for your website. It becomes rather clear after reading this article https://rush-analytics.com/blog/google-pagespeed-insights-vs-lighthouse-how-do-they-differ. The differences between PageSpeed Insights and Lighthouse are explained in an easy way.

My understanding is that "Page Experience" signals (including the new "core web vitals) will be combined with existing signals like mobile friendliness and https-security in May, 2021. This is according to announcements by Google.

https://developers.google.com/search/blog/2020/05/evaluating-page-experience

https://developers.google.com/search/blog/2020/11/timing-for-page-experience

So, these will be search signlas, but there are lots of other very important search signals which can outweigh these. Even if a page on John Deere doesn't pass the Core Web Vitals criteria, it is still likely to rank highly for "garden tractors".

If you are looking at Lighthouse, I would point out a few things:

• The Lighthouse audits on your own local machine are going to differ from those run on hosted servers like Page Speed Insights. And those will differ from "field data" from the Chrome UX Report
• In the end, it's the "field data" that will be used for the Page Experience validation, according to Google. But, lab-based tools are very helpful to get immediate feedback, rather than waiting 28 days or more for field data.
• If your concern is solely about the impact on search rankings, then it makes sense to pay attention specifically to the 3 scores being considered as part of CWV (CLS, FID, LCP)
• But also realize that while you are improving scores for criteria which will be validated for search signals, you're also likely improving the user experience. Taking CLS as an example, for sure users are frustrated when they attempt to click a button and end up clicking something else instead because of a layout shift. And frustrated users generally equals lower conversion rates. So, by focusing on improvements in measures like these (I do realize your question about large images doesn't necessarily pertain specifically to CLS), you are optimizing both for search ranking and for conversions.