Sanderson was fired on September 17, with two seasons remaining on his contract at West Lakes, before the club poached Walsh from Port Adelaide.
Sanderson's communication with his players was a key element in his downfall, although club heavies continued to deny his departure was player driven.
While Porplyzia insisted he enjoyed playing under him, he said Adelaide made the right call to terminate Sanderson's contract.
"I think towards the end there was a bit of a disconnect between the playing group and (Sanderson), and going forward I'm not sure if the club wanted to persist – it may have taken some time to rebuild things," Porplyzia told radio station 5AA.
"It was a fairly ruthless decision by the club, but I think the right call was made.
"The appointment that they've made in Phil Walsh is certainly a good one.
"I'm sure the boys will enjoy what he brings to the football club over the next few years, and I think they can look forward to a fair bit of success under him."
The 29-year-old, who booted 57 goals in a standout 2009 season, said he would now pursue a career in strength and conditioning.
After opportunity at senior level dried up in 2014, Porplyzia retired last Friday having played 130 games for the Crows.
He rated Neil Craig as his favourite Crows' coach, believing he played his best football under his tutelage.
Twitter: @AFL_Harry
