the "making tax digital” savings have been rated as “highly uncertain”
"highly uncertain"? HMRC can't even operate a telephone helpline to tell people how the current tax system works. (Either the phone bit or the 'explaining the tax system' bit)
Hands up anyone who seriously thinks that within 4 years they can "ensure the availability of free apps and software that link securely to HMRC systems and provide support to those who need help using digital technology." Which sounds suspiciously to me like rebuilding the whole machinery and legislation of the tax system and then offering device/hardware support as well as software support. Any volunteers to help man that particular helldesk?
Of course they won't *actually* provide device support, however much it might be needed, and however much it might be their fault that it is needed. Although if it all goes as well as Universal Credit then of course it probably won't be needed, or at least nowhere near as soon as they've threatened.