Starc, Australia's third-highest wicket-taker with 759 wickets across all formats, behind only Shane Warne and Glenn McGrath, retired from T20 internationals in September last year.
His departure has offered up a place in an Australian fast-bowling group long dominated by Starc alongside fellow pacers Pat Cummins and Josh Hazlewood.
Dwarshuis, who made his international debut in 2022, has featured in only six one-day internationals and 15 T20Is, competing for selection with fellow pace bowlers like Nathan Ellis, Xavier Bartlett and Spencer Johnson.
"There's a whole heap of Australian bowlers who have sort of sat behind Mitch Starc, Hazlewood and Cummins, who have just done amazing things for Australian cricket and haven't really opened the door for anyone else to take their spot," Dwarshuis said.
"Mitch retiring obviously opens up a spot. There's a whole handful of guys that are trying to get into that spot.
"Competition's fierce, but knowing that there is a spot available means a potential avenue there if you perform."
Dwarshuis, who was signed by Indian Premier League side Punjab Kings for a whopping 44 million Indian rupees ($472,000), said franchise leagues have become an increasingly important shop window for players chasing international selection.
The 31-year-old is the second-highest wicket-taker in the history of the Big Bash League with 164 scalps.
"Anytime you take the field and have an opportunity to perform, there's always going to be eyes watching, whether it's from Australia or other leagues," Dwarshuis said.
"With the viewership these competitions get, it's very easy to have a couple of good years and everyone's talking about you.
"But then if you're not performing well, that sort of viewership leads to maybe less opportunities there."
Punjab, currently fifth in the IPL standings, opened their campaign with a three-wicket win over Gujarat Titans, a match in which Dwarshuis wasn't selected because of the depth of the squad.
Asked what would be his prized wicket this season, Dwarshuis singled out India great Virat Kohli.
"There are probably six or seven Indian players I could rattle off," he said.
"But it's tough to go past taking Virat Kohli's wicket, whether it's at home or down in Bangalore. He would certainly be one I'd be happy to take."