I wanted to make a video about this but I honestly can't be arsed to, so I'll share this here instead.
It's my belief that this new update actually came with 4 new tracks and 3 new cars. As has been mentioned before, the Laguna update was 2.4GB so this one being 3.3GB is pretty sus. However, we don't know what methods PD uses to compress/uncompress the data and it could very well be that they have to release a new version of a track even if they just have to change some billboards. There are four tracks in the entire Olympic series, Tokyo South, Tokyo East, Sardegna, and Dragon Trail.
@Stephan also noticed that the steering wheel on the GR Racing Concept was different, using this same logic it could be that this is in fact a brand new car using the same car model, like the Gr.1/Gr.X VGTs. The same could apply to the 86 and the Yaris too.
Also, there's probably a new Olympics intro to be used like the FIA intros, knowing PD they probably made it 4k60fps super high bitrate etc...When I upload a 4 minute video in 720p60fps it's usually 200mb or so, not surprising that 4k might take about 800mb or so of space.
Also, after reading the 'Average Joe' discussion again, I do indeed think it would be a cool idea to have tier credit rewards and open up the olympics series as a 3-round FIA championship like the GR Cup, I also don't think that anyone is entitled to special treatment for being slower than others. Speed is only related to skill, not input device or console or software. It's a level playing field.
edit-If I’ve written this much I’ll probably make a video on it lmao