Cool! Thanks for posting.
I wonder what the rate of replication is for these bacteria, and whether they routinely go through cycles of DNA synthesis/genome duplication without dividing. It’s possible that this large number of genomes began as a consequence of defective bacterial replication, and is now retained because of the advantage this gives to a large cell for protein production. The point someone made about whether or not these genomes are all active is an important one. Probably not all are active at any given point in time.
Would the inactive ones "tar pit" a virus?