So let me get this right, now your babies are babies and most mums would stay home with them, you are going to work and when the babies are old enough to go to school, you hope to be a stay at home mum again??? That sounds a bit contrary to the norm but each to their own.
My experience tells me that once the family gets used to the money coming in, it starts living up to its income and its not possible to go back. Or something unexpected happens and things don't work out as you had hoped, i.e partners redundancy, caring responsibilities illness.
I think what numerous people are trying to counsel you on is that you shouldn't burn your bridges because life has a way of throwing curve balls and you don't want to self sabotage. Your confidence and innate belief in how your life will unroll could be your undoing. Have a fallback plan.
I'm not saying "she shouldn't take parental leave". I'm saying that before you have even started the job, you have already decided that the needs of your future colleagues are irrelevant, despite knowing absolutely nothing about them.
For all you know:
another colleague could be a single parent;
someone could have a child with additional needs;
someone could be caring for a disabled spouse or elderly parent;
someone else could already be making sacrifices to cover school holidays.
The irony is in your comments is that you are asking others to recognise that family commitments create genuine pressures, whilst refusing to recognise that other people may have equally valid pressures.
In reality, most workplaces find a way through these situations because people are willing to compromise. One parent takes Easter, another takes August. Someone swaps shifts this year because they know the favour will be returned later. Its may not be based around school holidays, it may be based around elder care, medical needs etc so don't assume there will be no issue outside school holidays. The legal entitlement is only part of the equation; cooperation is what makes it workable.
You also seem to be boxing yourself into a corner is things do not pan out as you project. When your children are preschool age, term-time constraints are often less rigid. Once they start school, suddenly the six-week summer holiday, half terms, inset days, school events and the inability to travel outside school holidays become significant factors. At that point you may find yourself relying heavily on exactly the sort of goodwill that you currently dismiss.
You hope be to a SAHM but you don't know if that is how things will pan out so be a bit more flexible in your vision of a relationship with colleagues.|
A workplace isn't usually a battle over who has the "best" reason for needing leave. It's a process of balancing competing legitimate needs. The fact that parental leave is a legal entitlement doesn't remove the reality that teams still have to function and individuals still have to work together.
My point is about wisdom and edging your bets rather than rights. Legally, you may be perfectly entitled to take every week available to you. But from a practical and human perspective, announcing in advance that everyone else's circumstances are irrelevant is unlikely to help you. As the saying goes, people remember how you treat them when you don't need them. At the moment you apparently don't need any favours, flexibility or goodwill beyond your statutory rights. But circumstances change. Children start school, childcare arrangements collapse, relatives become ill, emergencies happen.
I think you are getting stick on your attitude because there is a difference between: "I intend to use my parental leave entitlement because that's what works for my family" and how you intend to execute that when you add "I don't care whether that causes difficulties for anyone else."