Which sadly doesn't mean that they have a lot of experience in the algorithms involved when handling datasets.

Since when does every use of a database involve handling datasets in a way that needs experience and "algorithms". A key value store can be used as... a key value store if need be. It doesn't need to be crazy science.

Once you start scripting your K/V store, its not a simple K/V store anymore.

I am not against databases with scripting capabilities and I do not think javascript/front end developers are per se naive, but I've far to often seen the naive assumption that just because its javascript, everyone can handle it.

This isn't true. Once you have tens of thousands of records, a poorly written algorithm or data structure is going to lead to O(n^2) behavior. That hurts. Even small sites can hit this amount of database records with ease.

So if database developers have significant experience in SQL, they should author websites using templating engines that generate HTML using SQL?

(This is only partially sarcastic as there were a few RDBMS + HTML template products that mercifully died).