Pearce, who has picked him for every England Under-21 match since taking the role, said: "I've worked with Theo, he's a fantastic boy and very, very keen to learn.
"This season some people have told me Theo has not lived up to expectations - and some others have told me he's ready for the (England) seniors.
"He scores two goals in a Champions League game and suddenly people are saying 'oh yes he's ready, pitch him in, throw him in'. It's all boom and bust, but for me it's not.
"If you think about it, Theo is still playing two or three years short (of the Under-21 limit).
"He's the second youngest in the group but he's played every game for me, started every one and that will bear fruit in the future.
"Whether Fabio will decide to pick him in the squad for the next senior game I've no idea but if not he'll be in my squad (to play Poland in a friendly at Molineux) because it's part of his development.
"For what he's done for Arsenal so far this season I think he'll be quite entitled to say at the end of the year that having played 'x' number of games for them at 18 or 19 and every England Under-21 game, that his development is still going quite well.
"I don't really think everybody is clamouring for him to be included in the senior squad and if they were I still think he's level-headed enough to deal with it.
"It's all about trying to divorce yourself from the boom-and-bust, short-term mentality which has seen us get a bloody nose in this country so many times before.
"And I think we should congratulate people who give talent time to come through and progress slowly."