It’s very surprising they didn’t continue this style of meeting, some sort of internal IEEE disagreement seems the most likely reason to me, but the evidence is probably lost to time now…
Despite the apparently glowing write-up from the time, hailing it as a success, no doubt there were constant cringeworthy "technical issues", of crackly lines, poor volume, calls dropping off, etc - I can well imagine the organisers saying: "we pulled it off once, for the lolz, but only just... Never again!"