Regarding Matt Harvey and the Mets, it’s time to stop being polite and start getting real. Harvey’s right shoulder is stronger than ever? Mickey Callaway couldn’t overlook his upside? OK. Nothing is impossible. Yet after everything this pitcher and this team have endured and experienced together, they should aim lower, if only privately, in 2018. How about just trying for a graceful exit? “New year. People make mistakes,” Harvey said Thursday at First Data Field, in his first news conference of the spring. “I’m looking forward to a new season.” This quote came in response to a reporter’s question about the nightmare that was his 2017 — the dreadful results on the field and his memorable three-game suspension for failing to show up to a Mets game at Citi Field. It easily could have covered the myriad mistakes made by both him and the Mets since Harvey first electrified the fan base as the Dark Knight back in 2013. Harvey reported to camp with five years and 72 days of service time, so barring some unforeseen development, he’ll be a free agent at season’s end. Remember when he got mentioned right alongside Bryce Harper and Manny Machado (and the late Jose Fernandez, sadly) as someone set to strike it mega-rich at the 2018 Winter Meetings set, fittingly, in Las Vegas? In Thursday’s news conference, Harvey’s free agency didn’t come up until the sixth question. Shoot, if the Mets felt like saving a few more bucks this past winter, they could’ve justifiably non-tendered Harvey, who has a combined 5.78 ERA in 185 1/3 innings for 2016-17, and set him free a year earlier than scheduled.