Interim boss Lee Carsley, who will remain in charge for next month’s Nations League matches against Greece and the Republic of Ireland, led England to the European Under-21 Championship title last year.
England also won under-20 and under-17 World Cups in 2017, both following the opening of the Football Association’s national football centre at St George’s Park, near Burton-upon-Trent, in 2012, with the aim of developing a pathway for players and coaches.
“What the FA have built – and I was part of that and have seen first hand what they’ve built over the last 10, 15 years – it’s been great,” added Rooney.
“It’s been a great platform for young coaches coming through, so I’m surprised they haven’t gone in with one of their own.
“But they’ve made the decision and I wish him all the best, and I hope he does well for us.”
Rooney won 120 caps for England and scored 53 goals – a record mark that was only bettered by Harry Kane in March 2023 – between 2003 and 2018.
Rooney played in three World Cups and three European Championships, helping England reach the knockout stages five times as he played under six permanent managers including Southgate, Steve McClaren, Roy Hodgson and Sam Allardyce.
“I think it is slightly different when you go to a World Cup or a European Championship and you’re watching your [foreign] coach watch his home nation,” Rooney added.
“I’ve experienced that first hand and it’s not ideal.
“But I’m sure Thomas is very professional and he’ll do everything he can to help England win.”