Well it depends on how Microsoft's accountants manage the maths:
Hypothetically, if MS + Activision - UK > MS + UK - Activision (assuming it's only blocked in UK), it's plausible that Microsoft withdraws from UK to pursue its business with the merger everywhere else. The UK is a decent sized market, but it's far from the biggest.
Hypothetically, if MS + Activision - UK > MS + UK - Activision (assuming it's only blocked in UK), it's plausible that Microsoft withdraws from UK to pursue its business with the merger everywhere else. The UK is a decent sized market, but it's far from the biggest.