Infotainment systems are a race to the bottom on BOM+SW price point. ADAS OEM's understand that there is a human cost, liability, and reputational cost for failure.
The real risk with these monoliths is when companies start to remove the distributed/redundant nature of safety critical systems, in order to reduce hardware costs.
There are multiple very good reasons for a distributed system in a car. However, irrespective of how clever your architecture is, there is only one good reason for centralized systems in a car and that is cost. It benefits no one but shareholders and C-suite.
OTA updates are sold as a key benefit but again it's marketing, they only reduce costs for the manufacturers and effectively remove a lot of the penalties of recalls. I would argue that difficult/costly recalls put pressure on manufacturers for 'first time right' design, OTA favours happy-go-lucky software.