Yeah, there's a hack called " WurstLogo " that lets you customize the color and way the logo shows up, including an option where you can make it only appear when its outdated, but if it's in date, it won't be visible. Here's the Wiki description:
The “Visibility” setting in WurstLogo controls when the Wurst logo is shown on screen. When set to “Only when outdated”, the Wurst logo will only be displayed if the user is using an outdated version of Wurst for their version of Minecraft.
For example, if the user is on Wurst 7.27.3 MC1.16.5, it will not show the logo if a newer version of Wurst (e.g. Wurst 7.30) is available for a different version of Minecraft (e.g. Minecraft 1.19.3), but it will show the logo once a newer version of Wurst is released for Minecraft 1.16.5. The default value for this setting is “Always”, which means that the Wurst logo will always be displayed.