One possible take is that this is great for archival storage (write a lot, hardly ever need to read back) - I think that's totally possible... but then you are also sort of betting that the company is going to be around in 10 years? Or else you are going to be hiring a really weird data recovery service.
I think it's reasonable to project that DNA read/write costs could fall 10x or 100x in say the next decade but the technology already needs to do that just to be competitive with existing solutions. The company seems to be a bet that costs will fall faster than alternatives like LTO, which I think is a lot less risky to sign a cheque for and I can buy right now.