i haven't used malwarebytes all year, i hide behind ublock origin and don't download files from strange places, so I don't get malware. I use Bitdefender Internet Security so I expect it clears up anything I miss - its not as cheap as MWB but they do different things. I am not convinced you could run a PC without a better AV than defender and just use MWB, regardless of their advertising.
I can't offer a alternative that is cheaper or life time.