Only solutions I see are, having secure parking for bikes offered for pay, as benefit of employment, or venue provided. What makes a bike a pain to store besides length is the handle bars and foot pegs stick out. So design a handle bar with a pin so it can be rotated alone the bikes axis when parked and folding pedals. Then you can box store them narrowly akin to bus lockers.
Still the primary deterrent to theft is putting it where its at risk and if that means not taking it, well.
The economics are extremely simple: There is a significant market for "don't ask, don't tell [if they're stolen]" bicycles. The same probably exists for cars which is why it took immobilizers (not frame/engine serial numbers) to curb theft.
A further complication makes a bicycle immobilizer impractical: It is trivial and not even very conspicuous to carry a bicycle quite far, or stick it in a car. That allows you to remove the bicycle to a private location where you can remove or destroy the immobilizer - if you could do the same with a car, I'm sure immobilizers would be less effective.
> Step 4
> Recover Your Property
> If the police or a good Samaritan find your lost or stolen assets marked with our microtag technology and contacts MyDataTags, we will inform you and give you their contact information so you can recover your personal property.
So it's a serial number that nobody will notice (1mm black dot) or be able to read (I would assume it's gunk to be scratched off, not taken to with a magnifying glass).
Maybe I'm missing their key point, but on a bicycle the reasonable responsible buyer will just run the serial through whatever stolen registry is most popular in their area, not scour the bike for tiny secret illuminati codes.
There's not really an equivalent for that in bicycles - a vital electronic component that, if removed, makes the bike unusable. Sure, you can get a bike tracker on ebay, but if trackers were making a significant dent in bicycle theft, thieves would just look for them and remove or disable them. For trackers to get a signal the antennas have to be exposed, making it a simple enough matter to put a nail through the patch antenna.