Do workers 17-24 still provide additional minerals?

In WOL and HOTS, the optimum number of workers per 8 mineral patch base was generally agreed to be 24. Over the command centre, a number was displayed (23/24, for instance) indicating the amount of workers at that base.

In LOTV, that number is now 16.

The way I remember mining working in old versions, is that per mineral patch, two workers could mine at full efficiency, and the third would mine at approximately half efficiency. Beyond three, there were no further gains in mining rate. This is explained in this answer, and further elaborated on on Liquipedia.

My question is, is this number change from 24 to 16 due to a change in the mining mechanics, or due to a change in the meta of what it is generally agreed to be the optimum approach? Does saturating minerals from 17-24 workers still provide additional income at lower rates? What is the general approach in high level play?

I have noticed that modern maps are much larger and contain more bases. It used to be that you'd have your main, a vulnerable natural expansion and some high-yield minerals in the middle of the map, and that was it. Nowadays, maps seem to have at least three relatively easy to defend bases plus several more in neutral territory. I figure expanding to a new base is now generally more preferable to milking every last ounce of productivity from your existing bases. Would this assessment be accurate?

Solution 1:

Yes, additional workers still provide additional minerals.

DON'T do this. The mineral patches had their amounts lowered, to encourage more expanding. Like you said, the maps that are used have more bases and the strategy is to mine your expansions as fast as possible because they are harder to protect.