Just my opinion...
1. Takemura is Saburo's bodyguard, which means, he has certain responsibility to the death of his boss, maybe that's why he got his implants removed as punishment at first place, after he chased down the so called killer(V and Jackie), he will be restored his position and implants back, but we all know that's an excuse...
2. Also, Takemura is loyal to Saburo, which means he will do anything he could to find out the truth of the death of Saburo, that's a big threat to Yorinobu, and that's why he sent out those assassins to hunt them down...
3. CDPR put so many Japanese elements inside 2077, there is noway for them to let go the "ronin" idea...
4. Hanako is raised to be a "good kid", Takemura is raised to be a "good soldier", but only person try to fight the system is Yorinobu, that's why he ran away from home at early age, and decided to come back to destroy the system from inside, but he failed because of V, he is more like Johnny but with different character and different methods, a very sad story...
Put Japanese inside the game is no big deal, but it's kind of old, how many people today still believe Japanese companies could have such power in 2077? It's more like the idea from late 80s or early 90s, even Hollywood doesn't use this kind of idea anymore