The number of such mergers, globally every year, is countable on two hands. They involve the wealth of nations (this one’s similar to Malta’s GDP [1][2]).
It would be unreasonable to permanently staff the regulatory force that would be required to quickly review such deals in any industry.
[1] https://en.wikipedia.org/wiki/List_of_countries_by_GDP_(nomi...
[2] https://news.adobe.com/news/news-details/2022/Adobe-to-Acqui...