3kg bikes are not practical. But I'm pretty sure a complete modern (electronic groupset, disc brakes) circa 7kg steel bike would find buyers, especially as titanium bikes still do find buyers even at prices and weights both higher than comparable carbon bikes.
You could buy a 5.42kg steel bike with a carbon fork in 2019 https://www.bikeradar.com/news/worlds-lightest-steel-road-bi..., given that a regular steel fork is about 800g, even if the original carbon fork is 0g, you can throw in a steel fork for total 6.2kg. Disc brakes instead of rim brakes would be another 200g. Something tells me those don't sell very well though and the company had not been updating this model ever since. Looks like they've done it for publicity.
