Yes but politicians are not interested in the net cost years down the line, its the figures next quarter that count.
In the links you post, the Unions are against cuts to services, which is going to happen when we remove Care Work from the visa process, thats not pro immigration.
There are 135k vacant posts in Social Care, even with the visas, this isn't going to be filled by taking the long term unemployed, threatening them with sanctions and forcing them to do these roles.
It may well increase the retention issue as decent carers leave, unable to work along side people who shouldn't be in the role.
Increase pay and ex carers will return, the role consistently scores highly in job satisfaction surveys.