Chelsea, who sold the Belgian frontman to Everton in 2014, are said to be eyeing a summer swoop while Jose Mourinho's United also continue to be linked.
The Everton striker is set to quit the club this summer after refusing to sign a new contract amid reported interest from Europe's elite.
A report in The Sun claimed that the Belgium worldwide would prefer a summer move to United as he has reservations over playing for Antonio Conte at Chelsea due to his pressing style and the defensive responsibilities that come with it.
Meulensteen was assistant to Sir Alex Ferguson from 2007 to 2013, helping the Red Devils to three league titles and a Champions League crown, and believes that if they want to return to that level, they need someone other than Lukaku.
Meulensteen told the Alan Brazil Sports Breakfast:"Don't get me wrong here, Lukaku has obviously had a fantastic season and he is a goalscorer".
"I think Morata will suit Chelsea much better".
"As long as I didn't make a public statement about my situation please stay out of my business ok?" he wrote on Twitter late on Sunday night.
"Some media these days are annoying man", he tweeted.
The 25-year-old is on loan from Sassuolo, and has scored 12 times in 32 top flight games for Crotone, who, without his goals, would have surely been relegated many weeks ago.
But one can not help but wonder if Lukaku, after another prolific season, would really opt for remaining at Everton when a multitude of big clubs move towards him over the summer.