This is not so much an issue for buyers of "new" units... as for buyers of "used" units.
Rega seems to honor their warranty... but it only covers the original buyer. It you're buying a new unit from an authorized Rega dealer - you shouldn't be too concerned about Rega taking care of your unit, if you have issues with it.
But... and that's a BIG BUT... if you're considering buying a "used" unit (e.g Audiogon, eBay, Headfi, whereever), you should take great care - because your unit will not be covered under their warranty. You're "on your own."
Obviously... the frequency of the tracking issues (at least in the past)... presented a signficant risk to such a buyer (and still does)... and... likely an unacceptable risk. That risk, also, abnormally depressed the resale values of those "used" units. So, even if you bought a "new" unit... you were unnecessarily harmed by Rega's slow reaction to resolving the tracking issues - you couldn't sell your "used" unit for a reasonable market price, because of this unnecessary risk.
The original post was intended to inform potential buyers of "used" units, that they may encounter such a risk of tracking issues, as well as to alert buyers of "new" units, that they might not be able to resell their units at a fair price, when they decided to upgrade, because of this risk.
When they realize they have such a fundamental issue with their units, ideally, a good (honest / reliable) manufacturer issues a "recall" to resolve the issue, or at least agrees to honor their warranty, for any buyer of the affected units, whether "new," or "used." They acknowledge the problem, and support the resale price of "used" units by extending their warranty to those units. This is what Rega should have done... and... still should do. Its the fair and honest thing to do, if they care about good customer relations, as well as their reputation.
I have no idea, whether they've done that, or whether they've resolved the tracking issues in their current "new" units. But... there can be little rational disagreement that it should have been their policy to do so... if Rega is a reliable / honest manufacturer. If they haven't adopted such a policy... the fact that they haven't... should be enough for most prospective buyers to avoid any Rega product... unless they intend to hold their "new" unit... forever.