The problem is that it makes sense to focus on USB-C for any new purchases, as that standard is firmly entrenched now with no future changes/replacements on the horizon.
USB-A and USB-C coexist; people expecting USB-C to completely supplant USB-A anytime in the next several years (like the likely life expectancy of one of these docks?) indulge in a fantasy. An argument can be made for more USB-C and fewer USB-A, but for what these things cost, nobody wants to have to buy adapters and converting cables to use their peripherals.
On the 'future changes' end of things, there are already a number of different versions and issues with these things so there's already confusion. Consider...
1.) Not all USB-C ports can handle 10 Gbps data transfer rates.
2.) Not all USB-C cables are rated for the same data transfer rates or charging capacities.
3.) Some USB-C ports are for Thunderbolt, which further breaks into varied standards (3, 4 and 5), and each requiring a Thunderbolt cable to enable full functionality.
4.) A dock's USB-C ports may not support USB DisplayPort Alt Mode for video out, an issue I ran into with a dock hooked to my Mac, and a display hooked to my daughter's Windows PC.
There is no technical advantage to USB-A.
Untrue. As another post noted, with USB-A some circuitry can be put inside the portion that goes in the port, so USB-A wifi receivers and some thumb drives fit almost flush, with barely a 'button' protrusion, which not only looks better but is less vulnerable to getting bent and broken when a notebook is moved around, etc... For mouse and keyboard wireless receivers and some USB thumb drives, USB-A is superior.
The only issue is preexisting old devices, and for that we have the $ 1.00 solution:
That same solution can let you use your USB-C peripherals with USB-A ports on a dock!