I like these bottom up approaches, as they demonstrate very well how much we _don't_ know yet about life. Important to mention here Craig Venters minimal cell project syn3.0, where the team synthetically created a livable cell comprising 473 genes. It was done to a large part with trial and error, the function of many of those genes is still not known. A recent review from the same team is to be found at https://doi.org/10.1016/j.cell.2022.06.046 .
Not quite sure I'd describe that as a bottom up approach - they sell it as that - but in reality it's more like Jenga. Seeing which bits you can remove without the system failing over.
The technical fact that the genome was artificially synthesized is just showmanship - they still had to put into an existing cell.
It's like claiming you made a car from scratch by replacing a chip - which you've copied from the existing chip but left a few bits out - and now the indicators don't work, but you can still sort of drive.
