I say, decapitate! ;-) I am an avid pruner. I would cut just below the visible bend of the main stem. But in my opinion, the exact spot depends on the number of leaf nodes and how tightly they are "stacked".

Where to cut? Always cut where the leaf nodes (this is where future leaves will emerge) are "stacked" (see (1) below). Never cut where leaf nodes are more spread out/far from each other (see (2) below). This distance between two (leaf) nodes is called the internode.

(Btw, I have no clue, why I made those arrows below ;-) ).

But why do we like short/small internodes in the first place (= "stacked" leaf nodes)? Because 1) this is another way of saying, that the plant has a most desired compact growth form,

... and 2) pruning at such a sweet-spot (again, where the leaf nodes are "stacked") can result in several new branches emerging from that particular sweet-spot hiding the cut even from early on. On the other hand, if you prune at (2), you could end up with only a single branch emerging near the cut (= not very pleasing to the eye. Actually, you didn't achieve anything or very little).

Should they not wait until spring to prune?

Eeyore, I'm not sure but will wait until spring. Not now.

Thank you, Martin for the time you took to explain. Great! I see quite a few nodes on the trunk below the lowest leaf on the top part.

Wait until the seedling is growing/putting out new leaves.

It's putting out leaves now. You can see them at the top. I will wait until spring arrives (even tho' it was in the 80's today, technically it's winter. Ha ha.) Thanks, Martin.