Not new.
Parting out happens often with games predominantly due to lack of profitability within the general market. The wheels of time turn. This is more of a "phased trend" as it goes in cycles with pinball revivals when somebody is trying to cash in a quick buck. The numbers of EMs parted out today is a pittance compared to those that outright placed in landfills in the early 80s or the WPC games destroyed for their boardsets in the early 00s. Some titles have already been expunged completely from pinball history.
Save what complete games you can, but if not reuse the rest. I have squirrelled away my share of backglasses and parts as titles were prepared to be thrown out in dumpsters. If I tried to save every game in existence I ran into, I would have a full warehouse. Instead I try to pass the games onto people that I know will restore them properly, as I don't have the energy to do this anymore.
