However, there's a number of ways this situation could play out, and not all of them are equal in several ways. First of all, it's important to keep in mind Irving has very little actual leverage here - if actions speak louder than words, everything Dan Gilbert, owner of the Cavs, has done since the Golden State Warriors unseated his team as reigning champs has suggested he has no intention whatever of paying a large luxury tax bill if he can help it.
I am not opposed to being critical over how players and front office people working for him (or in general) do their job, but conversely, we are talking about an owner with no problem whatever doing anything he likes to protect his interests, and for now, that remains gouging the people of Ohio for free renovations far in excess what would have been lost had he followed through on his word. So, do not expect him to care about whatever Kyrie says he'll do - he'll be happy to let him look like the bad guy here. It suits him just fine.
There's a great chance Gilbert does nothing at all, waiting out Irving and hoping his star player solves the problem for him by leaving. For Boston's Finals aspirations, it seems at minimum the weak moves in the offseason to date (firing their GM as he tried to improve the team, not hiring another, resigning Kyle Korver, and inking the corpses of Jose Calderon and Jeff Green) plus this additional turmoil have already weakened the Cavs considerably even if no more moves come this season. But other options may prove attractive, and not all of them might be great for Boston.
For example, two of the teams (the Miami Heat and New York Knicks) are in the East, and while they would not directly impact Boston's title aspirations, improved teams in the East will have an overall impact on the final record that could be amplified with an unexpected injury - or slow recovery, should Isaiah Thomas need to go under the knife. The other two teams - the Minnesota Timberwolves and San Antonio Spursmight have the opposite effect on Boston's standings, but depending on what Cleveland gets back, might also minimize any gains in at least the short term the Celts could hope to get from such a trade, particularly if the team defense is improved for the Cavs.
"The Boston Celtics could offer point guard Isaiah Thomas, who was chosen for the All-NBA second team last season (Irving missed out). Thomas is surely the closest offensive proxy for Irving's skills the Cavaliers could get in return. However, the Celtics might be willing to offer him because Thomas is an impending free agent and his defensive limitations (in his case, being 5-foot-9) are more difficult to overcome."
There is also the possibility of trading LeBron James himself, who is almost certainly leaving, allowing Gilbert to retain some of his still-immense value even this close to free agency. Of course, this is even more of a moot point than Irving given James' no-trade clause, but presumably a deal might be reached for a sign-and-trade to an amenable destination, given how few teams are likely to have cap space of any significance on a timeline favorable to LeBron's advancing age.