Not, read RD 743 and associated implementation papers carefully, some even believe it just "grandfathers" the cancelled "not remitted in the year of earning" exemption, so I believe it could end up that way.
And it would make sense from the Thai (Finance) point of view; if the average LTR retiree makes 100k USD this could be, for every 1000 visas, 100 Million USD (35 Billion THB) brought into the country every year.
Ok, it maybe wishful thinking on my part, and as someone pointed out TIT and thing never make sense, but on the other hand I have found BOI to be quite impressive.
An other thing gives me that nagging feeling this could be the case is that, last September, when people started querying BOI about remittance tax there answer was "remitted income not taxed". And we now for sure that global IT was already considered at that stage, the first article on the September changes here was mentioning it.
And last, wouldn't that be exactly BOI's mission? Otherwise why would they deal with retirement visa?