That's just the inbuilt software to prevent burn in issues, all modern OLEDs from LG, Sony and philips has similar named software to prevent burn in. Its been this case for past 2-3 years LG who make the OLED panels are very confident that burn in should not be possible especially on 2019+ OLED TVs.
I googled it and could not see Philips offering any burn in guarantee though.
Finds, analyses and reduces light for logos
www.whathifi.com
LGs has the same tech its called logo luminance software. Sony has its own version etc
Am really unsure what Richer sounds is doing, they apparently were considering burn in insurance but then did not bother its possible they thought since LG are this confident now that burn in wont happen that the insurance was pointless.
I would have preferred they offered the burn in insurance since there is no guarantee with any tech and if Richer sounds wants to compete with John Lewis they really should offer it.
£140 john lewis insurance imo is far better then jumping through endless hoops asking Richer sounds or Currys can you help with my hardware TV fault (burn in or similar) and being told we don't cover it.