They will try, but anti-trust laws and -lawsuits should compel them otherwise. Microsoft had to pay hundreds of millions in fines to the EU for not complying with a previous browser choice order [0], following previous lawsuits in the US about their tight coupling of Internet Explorer [1] in which they settled for $1 billion. Google has to pay a fine in excess of 4 billion (!) to the EU for anti-competitive practices in Android [2].
This does raise a very interesting point though in my opinion. There's been some debate about whether Google should be compelled to sell off its chromium browser, but I wonder if it makes more sense to spin off Google's various attempts at boning internet infrastructure such as AMP and 8.8.8.8.
I guess AMP is being wound down but it was a play for shifting more of the Internet onto Google infrastructure.
[0] https://ec.europa.eu/commission/presscorner/detail/en/ip_13_...
[1] https://en.wikipedia.org/wiki/United_States_v._Microsoft_Cor....
[2] https://en.wikipedia.org/wiki/Antitrust_cases_against_Google...