For me the breaking point was the first half of Matt Smith's second season, i.e. the "i-cant-believe-its-not-slendermen" season since thats when it became really fuckin apparant that major plotlines and changes to the status quo were being casually abandoned, forgotten, and entirely contradicted on a writers whim, with the last episode I watched before tuning out being that craptastic "mass produced clones in a castle" episode, and the last episode I halfway enjoyed being the Nixon episode at the start of the season.
I still watched the occasional episode afterwards, and even enjoyed the 50th anniversary special enough to consider it one of the main highlights of the Nu-Who era but...yeah that was pretty much the last time the show ever got my positive attention. Capaldi's introduction was cringetastic as was his characterisation of the Doctor despite me having fairly high hopes for him and only got worse as more episodes came out and his "sanctimonious old douchebag trying to be kewl for da kidz" schtick grated on me ever more....then the fucking Moon Episode happened and I officially stopped watching the show forever because holy shit its been five years and I still cant quite believe how bad that shit was.
Honestly there is no fucking salvaging it anymore. They could dump all the SJW schtick and it would still be a badly written obnoxious mess. They could change all the writers and the new ones would still be handicapped by all the shit that came before unless they do some contrived "universe reboot" shit. Its time to put the show in the ground for another twenty years and hope something worthwhile rises to replace it.