Stewards said Piastri was "wholly responsible" for the incident, and gave him two penalty points on his licence in addition to the time penalty, but the sanction has been criticized by fellow drivers Carlos Sainz and Charles Leclerc.
"Fortunately for me, a lot of people have done the talking for me," the Australian told reporters on Wednesday ahead of this weekend's Las Vegas Grand Prix.
"I think when one of my fellow drivers is involved in the accident and says it's not your fault, I think that's a pretty good indication."
Piastri served the penalty for the early clash with Mercedes' Kimi Antonelli, which put Ferrari's Leclerc out of the race. Piastri went on the finish fifth in a race won by teammate and title rival Lando Norris.
The 23-year-old said he and McLaren would seek clarification from the FIA on how the stewards had arrived at the decision and whether the penalty guidelines needed to be reviewed.
"It's something that I'm sure we'll talk about with the FIA, just to get some more understanding," he said.
"I think it was a bit of a surprise for everyone here that this penalty was so harsh, myself included. So I'm sure we'll talk about it."
Piastri stressed he was not looking for an immediate rule change but wanted to understand the reasoning behind the stewards' call in a bid to improve consistency.
"The only thing you can do in these situations is try to learn the reasoning and thinking behind it and whether that needs to change or not," he added.
Previous discussions between drivers, teams and officials over incidents and penalties had generally been constructive, and he expected the same this time.
"It's been very receptive to that in the past, and I'm pretty sure it will in the future," he said.