May be worth noting that JET (Blue) used by Exchange is a very different beast to JET (Red) which is used by Access.

Both JET projects started in the late 1980's. With Blue being Transactional & Red smaller footprint. So really this original editorial had little to do with MS-Access.

But you are correct in stating that most in the SQL team & may SQL folks would prefer that Access apps used SQL as its native database. Most Office folks would see its future differently. They align its capability closer to Sharepoint. (Worth mentioning that Sharepoint uses SQL. So over time this integration may still happen. Especialy as SQL incorporates some of the ease of deployment features that Access desktop users desire.