The UK has had unacceptably high rates of stillbirth, more than comparable populations and comparable health systems. There has recently been much work done on addressing this issue and new practices and guidelines are being developed. They know that one of the risk factors for stillbirth is being an older mother. That is if you have women with otherwise identical histories and profiles and pregnancies, the babies of older mothers are more likely to be still born than the babies of younger mothers. There is no way though to know which of the "older" babies will be affected and which will be perfectly fine. But we do know that as a group, their risk level is greater. So one recommendation to deal with that risk for that group of babies is to induce at term. Once the baby is term, there are no additional health benefits or developmental stages that are improved by remaining in the womb, and the risks of placenta failure and other risks increase. And in general, for this group of babies, the risks of induction at term are less than the risks of watchful waiting. So while of course it's true that the recommendation is based in your age, it's not just because somebody somewhere thinks old = bad. It's because evidence shows better outcomes for the induced babies and thier mothers, than the non-induced. Tools like additional scans in later pregnancy also help them refine your personal risk profile and allow them tailor a recommendation to you. But it is still a generalised recommendation, based on the best available evidence, not a crystal ball.
Of course it's entirely up to you to consent or not, but it is important you understand fully. Many of the measures to tackle the stillbirth rate are very recent so posters whose pregnancies were even just a couple of years ago may have had different treatment.
While I know it is disconcerting and disappointing to feel like you are shifting course mid-stream, I would encourage you to talk through any doubts or questions very seriously with your doctor. Then you will have the best information for you, and can make an informed choice.
For what it's worth, "being consigned to bed for days until the induction kicks in" doesn't at all correspond with my own experiences of induction, but of corse everyone is an individual and there are a variety of responses to and experiences of induction.
Best wishes. It's good that they are monitoring you closely. How you choose to use that information from extra monitoring is entirely up to you but please ask your medical team all your questions and make sure you fully understand so you can make an informed choice.