Frankly, CPU-hours and TB-years are still within 5-10% of the total cost providing sequencing results to the patients. What is really important is that the cloud allows us to determine exactly our cost-per-analysis without paying for excess capacity or maintenance.
What matters also is reliability, redundancy, and peak capacity, where the cloud (both Google and the other provider) win hands down.
Disclaimer: I work on Compute Engine.
Taking this to the extreme, you might even fire up a Windows VM so you could run some analysis or reporting tool there (say, Tableau), within GCP and then only need to egress the Dashboard or Report that it generated. You'd still have the raw data, but you would only be paying to store it. Especially if you're only keeping it around for archival purposes you could put it in a Nearline bucket and really minimize your costs.
(note: I work on GCE)