I'm quite confused that this has become a "thing".
Before buttons were invented, shirts were laced up and the necks gathered by tying together the open neck bit. How you tied it together changed over the years, from leather laces to scarfs and lengths of cloth. All of these were "ties". The practicality of it was obvious but also, as with every clothing choice, the richer wanted some way to look nicer and so they took to using different materials and styles.
Once buttons and pins were used, neck wear became purely decorative but also completed the look of a bare short front. Bow ties, usually reserved for special occassions, are a good example of how a tie can finish off a shirt front. But ties are secondary, hence why they are not garments but accessories.
The shape, length, girth and material change with fashion trends yet older gentlemen still prefer longer, wider, single coloured ties which carry down over the bellies, creating a slimmer appearance (instead of having a shorter tie bounching around on top of your gut). They also help to hide button bulge when sitting down.
Alluding to phallic shapes or that they are pointing to the crotch area just seems like a lazy argument.