This is certainly exciting news.
The 3 Series has had a long history of motorsport in BMW's racing portfolio.
The most recent 3 Series BTCC racecar, the E90 320si, even yielded a homologation special, complete with BBS wheels (inscribed w/the words 'BMW Motorsport'), a carbon fiber head cover, and an engine that was produced in the same Landshut foundry as the contemporary BMW Formula 1 engines and the later S85/S65 engines.
Yeah, in many respects, the street version was very modest (and prone to engine issues) compared to even other 3 Series models, and especially to the racing car, but it's still a cool car nonetheless.
That said, it should be noted that the photos in the OP are renders that are for reference only.
The renders were produced by the graphic artist Nick Moss, who specializes in applying digital motorsport-inspired modifications & livery on an array of cars.
So the photos are not meant to be seen as any sort of official visual design cues.
Therefore, it's important not to get overly excited or overly disappointed about any facet of the design or livery at this stage.
I'm not saying some of those details won't be close, but the renders are simply meant to provide a visual supplement to the news article that is that there are plans for the 3 Series to make a return to BTCC.