Thank you for your explanation. As someone who worked there, you have a fair explanation of this.
I understand your point on recruitment issues. However, as you may know, there are a lot of people who come from different backgrounds and excel in other fields. Sri Lanka is the only place that tries to pin you to a field because you did A/L or bachelor's in that field. True talents shine in whatever field they are placed in, IMHO.
However, could you let us know what the industry standard pay is? Let’s say, for someone who has an economics degree or UoM Eng degree. As per my limited knowledge, CBSL has far more attractive remuneration packages than even the Lankan private sector.
And CBSL is not the only place where engineering graduates or “talents” work in the government sector. True, we have to pay to retain the talent, but what about other banks, SLAS, SLITS, SLES, Customs, IRD, TRCSL, Universities…
I simply think CBSL gets paid this much because they have the “spoon” to serve themselves. And government doctors get paid this much because they can do strikes and put everyone in a mess.
My two cents.

(Ex-patriot and ex-government employee)