Which is at least partially why the only character to undergo this more-or-less unwillingly is Pathfinder Ryder, and for that matter, the Human Pathfinder is the only Pathfinder whose SAM has this level of symbiosis. The SAMs that the other Pathfinders have access to are basically overglorified VIs.
The thing regarding the Zha'til, tho, is that not only did the takeover get prompted by the Reapers, but the Zha'til developed the AI fully first, and only then did they attempt synthesis with already mature people. SAM, by design, evolves via his connection to the Pathfinder, and moreover was more-or-less raised alongside the Ryder twins as part of the family.
I suspect one optional choice made in this game that'll have huge consequences for this relationship down the line will be the reconfiguration of the Pathfinder VI in the cultural center, specifically the choice of talking about SAM vs talking about the squad. Future Pathfinders that are more comfortable with the idea of being linked with an AI will probably result in a stabler overall relationship between SAM and the Initiative, especially considering the inevitable necessity of more and more people being linked to SAM in this manner to facilitate interaction with Remnant hardware given the events of the game's conclusion.
Ergo: ME:A as a series is probably an effort on the part of the writers for not only justifying Synthesis as the "Best Ending" of ME3 but selling the idea in a way that's done far more ethically than "force synthesis on every living being in the galaxy." In this sense, the only person who has this actually forced upon them is Pathfinder Ryder, and it's not nearly as much of a shock due to their prior familiarity of working with SAM.
