One thing missing from this discussion is the effect of the well-established exam-based credentialing system on the profession as a barrier to entry. Does it counterbalance at all the kind of ageism that folks working as 45+ software engineers sometimes encounter? This is a sincere question, as I can also would not be surprised if insurance companies' CFOs would be the _first_ people to recognize the additional costs…
In general, companies don't deal with rising healthcare costs by hiring younger, less experienced workers. Instead, they restructure their insurance plans to alleviate the increase in insurance premiums. This part of what health actuaries (at least on the consulting side of things) do on a daily basis.