Not worth buying a new TV over, Dolby vision is arguably superior to HDR10+ anyway
After content is color-graded in HDR during the final steps of the post-production process, colorists have three primary HDR formats to choose from to deliver their final vision to consumers: HDR10, Dolby Vision, and HDR10+.
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Conclusion
Although there are clear distinctions between how HDR10, HDR10+, and Dolby Vision function, the visible difference between the three formats heavily depends on your display's content and capabilities. It's easy to say that Dolby Vision is the clear winner here since it offers colorists more tools that can lead to a better image when watching content at home, but not all HDR content is created equally. Oftentimes, the colors and highlights in HDR content aren't pushed very far, so there's barely any visible difference between the three formats with the same content viewed on the same TV, since HDR is so dependent on the content itself.
HDR10+ and Dolby Vision offer very similar advantages when streaming your favorite shows and movies since the dynamic metadata of those formats is the main component that sets them apart from regular HDR10. The impact of the dynamic metadata found in HDR10+ and Dolby Vision is greater on low-end displays since budget models don't come close to matching the capabilities of a mastering monitor, and your TV needs to try to fit the parameters of the content you're watching within its capabilities. With higher-end TVs that have similar capabilities as a mastering monitor, the dynamic metadata doesn't make nearly as big of a difference. However, with content that pushes HDR to its fullest potential, you can start to see some of these visual differences on any television, since no TV perfectly displays all HDR content.
