There are people who have been marginalized from sustainable attachment to the labour market by reason of family structure or by reason of disability who need not be marginalized from the labour market. The recommendations that we've put forward are very modest and practical, but at the end of the day they build on a knowledge we have that every person with MS wants to work, but the reality of our systems--public transportation, attendant care, and home care supports--are such that in fact people are prevented.
They make choices about going for disability benefits at a much earlier stage of what is a progressive disease in the context of MS. While they might be able to work 15, 25, or 30 hours and be gainfully employed and pay taxes, which is to the heart of the your question, they make a choice of being full-time on a disability benefit. They lose the social value of work, the motivation that comes from it, but more fundamentally they lose the opportunity to contribute as citizens productively to our economies and to the tax base.
To your argument, I'd say this is something you need to look at in an integrated way. I believe there are a lot of people who are marginalized from a sustainable attachment to the labour market not because they don't want to work or they can't work, but because the system prevents them from making that choice.