The important paragraph, is in section 6.6, for pensioners;
"The government does not intend to raise taxes on vulnerable groups or in situations where the UK is the principal taxing authority and an individual has no recourse to relief as a result of the UK having sole taxing rights under a tax treaty. If the government were to restrict non-residents’ entitlement to the Personal Allowance, it would intend this to apply to types of income which are taxable both in the UK and overseas (such as that from immovable property) but to retain the Personal Allowance on income that is taxable exclusively in the UK."
Section 6.5, is an important explanation for people renting out property in the UK;
"There are around 175,000 non-UK resident taxpayers with rental income. Non-resident landlords will generally be taxed on their UK rental income in their country of residence as well as the UK. Although some may currently not need to claim double taxation relief as their UK income is below the Personal Allowance, many non resident landlords would be able to claim double taxation relief and so should not face an overall cash loss without a UK Personal Allowance."
Section 4 and section 5.2 discusses determining your country of residence for tax purposes by a percentage income rule. I t discusses a 75% or a 90% rule, which means if you main income is above one or the other of these from a particular country (UK or another where you reside) then that is the country of residence.
You do need to read the full document, its not that long, as there are different scenarios which helps to explain some things.
This is far from being law at the moment, its just a consultative document which probably won't happen, at least not in the life of this current Government.