The 38-year-old Beckham, currently at Paris Saint-Germain, announced he was quitting football on Thursday having made 115 appearances for England and 394 for Manchester United, winning six Premier League titles and the Champions League.
Neville played with Beckham for 10 years at Old Trafford and was in Paris to chat to his close friend on the day the retirement was revealed.
"You think about how much football has changed with the introduction of the Premier League and all the TV and he's been the most influential player out of England in terms of transforming football," Neville told Sky Sports News.
"He's played in Madrid, Los Angeles, Milan and Paris and has transported England around the world. It was something he was aware of and something he always wanted to do. His impact has been enormous.
"Every single new hair cut or clothing garment has always been followed. And we're talking in football and out of it. He was an Olympic ambassador, an ambassador for Chinese football and he's also a Sky ambassador."
The news comes just over a week after United manager Sir Alex Ferguson and midfielder Paul Scholes stated they would also be stepping down from the game.
"It's the end of an era and the most successful era of one football club with United," added Neville who stopped playing in 2011. "Fergie retiring was a huge moment in football, then Scholes and now Becks.
"It does feel like the end of a generation and the end of an era. Football goes on but you will always look back at this period and think of these hugely influential characters."
On the reasons behind Beckham's decision, Neville said: "I think he just feels it's the right time. He feels he's taken football as far as he can and he's been away from home for 22 years.
"In 1991 he came to Manchester and now he's got to the end of the road but he's ending on a high at PSG with another championship. That's four in four different countries which is incredible.
"You look back and you think what an amazing array of caps and medals and the longevity of his career. You speak to him and he just wants to be remembered as a hard working football player and that's what stood out during the chat I had with him. Plus the fact that he gave it his all and worked as hard as he could to be the best he could be."
The Leytonstone-born midfielder has played for United, Real Madrid, LA Galaxy, AC Milan and PSG, lifting 19 trophies including 10 league titles.
Regarding Beckham's next move, Neville said: I've got no idea and I don't think he does either. He'll spend time with his family and he'll have some commitments and try to keep busy.
"He's spoken in the past about owing a football club but he's said he doesn't want to be a manager or go into media. He won't know whether he misses the adrenaline of football until July when all the players go back to training. Maybe we'll see him back on the pitch again in August!"
Beckham will complete his five-month contract in Paris and has two more games to go before the end of the season, concluding on 26 May at Lorient.
"He'll be emotional when he plays his last match and then he'll recognise that this is really it," Neville stated. "But it won't be just the match - it'll be the fact that he won't be going into the dressing room. He loved the banter and the camaraderie and he'll miss that the most."