The truth of academia is that it is extremely slow. there are less than 20 minds total on all of earth working on this idea, separately, in different countries. And these 20 people are in their 20’s, severely underpaid, don’t necessarily have all the resources they want, and science may not be their #1 life priority.
anyways:
reading and writing DNA is the main driver of evolution, and it does so because it is error prone (causing mutations). You can imagine this is bad if you want to preserve the integrity of the data.
DNA storage would be okay if you were to… say archive the entire internet for future generations, or geneology records, etc. things that do not need to be written and accessed quickly or often.