It is a worry isn't it. I feel the same about my mum. She only went out with us, or to day centre but she used to come to supermarket with us each week and we used to go for a walk to local shops and things, but now she doesn't go out only into garden and some days not at all. When we're allowed out will she be fit enough to and will she have confidence to go out,or will she get used to being at home and be scared of going out?.
Last summer she wasn't well with tummy/bowel problems for about 12 weeks and barely went out. It took quite a while to build her strength up so she could walk for longer than ten minutes, although a lot of that was down to her barely eating and she'd lost quite a bit of weight but some of it would have been down to lack of exercise too. She doesn't want to go out just to walk streets without somewhere to go although I'm going to keep suggesting it, as I'm worried she lose her strength again.
She struggled a bit at shops with paying/packing before so after long period of not doing it will she be able to manage it again? It also took a lot of time and work to get her to go to day centre and she'd only been a few times when it closed so not sure if she'll go back when she can.
Being in the house all the time not mixing with others outside of immediate family/carers and not doing much probably won't help, as well as the worry from seeing things about virus on TV etc all the time.
It's a new routine to get used to now and it'll be a new routine when things go back to normal and that will take some getting used to and as dementia progresses I wonder if all this will speed up that progression.
For people who work and are now at home I think it will be harder once their PWD gets used to having them around all time to get used to them not being there again. Its definately a hard worrying situation x