The 23-year-old Wales forward has scored 11 goals during his season-long loan at Portman Road from Premier League side Leicester City.
"I think Tom will have his heart set on the Premier League and I think he'll get that," said McCarthy.
"If Leicester are going to sell him, there'd be a lot of takers."
He continued to BBC Radio Suffolk: "Tom has been brilliant and we've all loved him, everybody's really appreciated what he's done, but I think he has his heart set on Premier League football and why wouldn't he?"
The Tractor Boys were assured of Championship safety thanks to Easter Monday's 3-1 defeat of promotion hopefuls Newcastle United.
And McCarthy hinted that there could be a large turnover of players this summer as the club go into their 16th consecutive season in England's second tier.
McCarthy said: "It's been tentative before being completely safe. I'll sit down and talk to (owner) Marcus (Evans) now about what we want to do and hopefully we can come up with something.
"But there's a real opportunity to freshen it up because there are a lot of players out of contract and we've quite a few players on loan.
"Do they want to stay? Do we want them? Can we have them? Can we sign them? There's all those things. We'll be losing a few players."
Championship side Ipswich Town have "no chance" of signing on-loan top scorer Tom Lawrence on a more permanent deal, according to manager Mick McCarthy.