their housing and public transport investment
Housing? I see you were quick to swallow the propaganda. Perhaps you should begin by reading this: money.pl/gospodarka/mieszkanie-karczewski-przyznaje-ze-program-nie-idzie-dobrze-6385886141905025a.html - even PiS themselves are admitting that it's been a failure.
Public transport? You mean the way that it was promised to be 800m, now it turns out to be only 300m? Still, perhaps you prefer this - nczas.com/2019/05/10/pis-swoje-zycie-swoje-padl-ostatni-panstwowy-pks-na-pomorzu-zachodnim/ - ah yes, PiS were very quick to help public transport ;)
will turn their social spending towards investment in health and education.
Let's begin by looking at the NIK report into schools, shall we? As we can read, it was poorly prepared and has resulted in significant costs for local governments.
nik.gov.pl/aktualnosci/reforma-oswiaty-w-czesci-sfinansowana-przez-samorzad.html
Perhaps you prefer to talk about hospitals?
prawo.pl/zdrowie/wzrasta-zadluzenie-szpitali-dane-za-2018-r,385528.html
Oh, hospital debt in 2018 increased by 600m złoty. 5000 beds vanished over a short period of time, too.
Ah, the glorious successes of PiS. 500zł a month won't make up for failing hospitals, public transport, schools and more.