I confess I don't really understand. At issue is the criminalisation of local governments and other bodies, such as student unions, boycotting certain products, mostly agricultural produce grown in illegal settlements. Nobody, to my understanding, has actually proposed boycotting all Israeli products. However, even if they did, the types of organisation that are under discussion are not able to dictate which medicines are available on the NHS.
As to whether any individual feels strongly enough about boycotting Israeli products to not use a drug that could save their lives, well, that's up to them and their consciences I guess. But that's not relevant to the legislation?
I'm sure I'm just being dumb, and missing the point here somehow.