Like the rest here I think ageing does happen in spurts and there is even some studies to back this up I've read in the past.
I think for women perimenopause and menopause is probably the biggest issue. I think your collagen production slows down even earlier in your 30's. Then the slow decline continues until you hit menopause and your collagen and skin density falls off a cliff! That is also when you really see the effects of habits like smoking, sun exposure, stress, bad diet and so on really show up as your youthful hormone profile stops compensating.
I started HRT at 43 and am not yet post menopausal at 46. Initially the HRT along with some dermal needling really seemed to help my skin but just this past year I felt like I was looking and feeling worse so I have upped my dose and things seem to be better now and as well as doing dermal needling I've added in an LED mask, and a growth factor serum and will probably do a TCA peel before the summer. It feels like every couple of years what I was doing before just isn't enough anymore. I've already been doing tretinoin for 23 years and SPF all my life, I've never done sun bathing, never smoked and I haven't had an alcoholic drink since I was a 18.
I think my skin looks alright for my age but there is always room for improvement. I've read that you need to start with "collagen banking" which you do prior to your menopause to compensate for the loss as you get older but I don't know if there is any science to back that up or if its just a way to sell women more treatments.
I am interested in interventions like radiofrequency, microcurrent and the newer injectables like the polynucleotide but I'm still looking into all that. I do do some guasha lymphatic drainage and I think it does help and some facial exercises but I never know how much good it does as every face is different you probably need to take care of how it is affecting you. For example I've seen some bad results with the oralift device.
There are also supplements and dietary changes to make, I've veggie and cook everything from scratch with loads of fresh fruit and veg but I've got a sweet tooth and I don't drink enough water.
I know people will say its natural to look older as you get older and of course it is but their is new research that actually links the health and aging of your skin to how you are aging internally and your health as you get older which means that doing what you can to look younger (within reason) and maintain your skin is actually a pretty smart thing to do to protect your overall health and longevity and looking better for longer is just a bonus.