I don't think "the world accepts it", but they are resigned to the fact that the moneyed interests powering these events are unstoppable. Which may or may not be true. Some of the opposition is even tactically waiting for the best time to make a stand - which might well be when the country is most exposed. See for example how the Yemeni Houti rebels tried to hit a Formula E event in Saudi Arabia with missiles.
The worst thing, imho, is that Qatar is not even remotely the worst actor in the region. A World Cup in Saudi Arabia might well be inevitable over the next 20 years, and that will be even worse.
The world could easily pressure Qatar into abolishing this, but it does not do so.
We're speaking of countries that were willing to wage costly wars on flimsy evidence of w.m.d.'s, that are now not willing to pressure a nation over real evidence of slavery.
One of those countries refuses to enact a reasonable minimum wage to this day. That one in particular has no issue whatsoever with treating labor poorly.
The US could indeed pressure Quatar over slavery, or Saudi Arabia over Khashoggi and human rights, or China over Uighur Muslims and emissions, or Russia over Ukraine and corruption, or Iran and North Korea over nuclear weapons, or Israel and all its neighbours to get a move on with the peace process, or the UK about the Irish border and laundering Russian money, or Mexico about border security and the drugs trade, or Myanmar about restoring democratic rule, or Japan about whaling or Turkey about treatment of their Kurdish minority.
But pressuring them all at once, and hard enough to get results? That could leave the US in a lonely spot.
The worst thing, imho, is that Qatar is not even remotely the worst actor in the region. A World Cup in Saudi Arabia might well be inevitable over the next 20 years, and that will be even worse.