Irrespective of the settings on my devices - laptop or smartphone - I have low confidence that my use and data is going unrecorded in some way.
Duplicate devices may be sensible - one for formal and largely unavoidable activity - eg: banking, tax, medical records - and one for all other activity - web searches, downloads, online shopping, forum and chat sites etc.
The duplicate needs separate emails, passwords, and ideally a second address (or no address at all).
I would also be a happy buyer of software which could emulate online activity based on spurious and random interests - perhaps in my case ballet, dog training, hip-hop music, lawn tennis, and roman catholicism, none of which I have any interest in.
There may be two ways to resist the march of "big brother" - either an obsessional level of attention to settings, software updates, permissions, cookies etc, - or simply neuter and overwhelm those monitoring use with excessive, spurious and irrelevant data.