But the club's Sporting Director says the Black Cats are in a strong position and has challenged the 20-year-old to fight his way into the Championship starting XI next season.
Neil had an outstanding, breakthrough campaign on Wearside this year, sealing his return to the England youth set up.
Speakman says having players who could attract significant bids is a sign of progress.
Sunderland announce young trio sign first deals with club
Sunderland transfer news: Former Black Cats star ‘open’ to SoL return this summer, Millwall ‘pull out’ of race to sign £2m Aberdeen ace
Newcastle United given green light to bid for winger
Arsenal negotiate 'significant sell-on fee' into defender's Sunderland contract
Sunderland AFC transfer rumours: Leeds United defender set for Championship move, Fabio Borini report plus Cats face competition for Jack Rudoni
“Dan played for England Under-20’s against Germany about four weeks ago," he said.
"By all accounts, he was the best player on the pitch from the reports and the people I have spoken to. That’s the calibre of player you are talking about.
“If there is not interest in Dan Neil, I’m not sure what the other clubs around the country are doing because he is a top young player. But he is our top young player. We’ve got him contracted and we love Dan Neil so at the minute, that is where Dan is at.
“Dan wants to play at the highest level. We have just moved to the Championship. It’s on Dan to get back in pre-season and get in the starting line-up.
“What a great position for us to be in that we’ve got those talented young players.
"I think Dan is one of a number of players that are in that bracket where other clubs are going to be here, watching him.
"We can see the list of scouts that turn up every week, we know they are coming to watch and we think we have got four or five that are in that bracket.
“That is completely different to 12 or 18 months ago. We have some real, if you wanted to, saleable assets in the group. I think the nice thing about saleable assets is that you’ve got some good players."
Neil was one of the youngsters who Alex Neil felt was at risk of burnout when he arrived at the club, and his playing time subsequently declined in the closing stages of the season.
He did, however, score an utterly crucial goal against Crewe Alexandra at the Stadium of Light to significantly bolster the team's play-off hopes.
That was a reminder of his talents and Speakman insists that the final weeks do not take the shine off what was an excellent campaign.
“The league is different as well so the qualities you might need for certain games in this league [League One] might be different to next year and I think there is a big difference in terms of the styles of football, which is fine," Speakman said.
"That’s the challenge.
“I think if you sat down at the start of the season and said Dan Neil would have played the minutes he has played, I think he is in the top five for us even at the end of the season, everyone will have been delighted. I just think the sequence has been the wrong way around and people question it.
“Dan did incredibly well and performed at a really high level when we really needed him to," he added.
"He got us points and helped us to be part of a successful team when we were missing some of the players.
“Naturally, Dan is a first-team footballer now so Dan’s not an academy player. He’s come from our academy but he is now a first-team player.
"Therefore, his task is to try and work a way to get into the team and we’ve had a winning team. Therefore, it becomes difficult for anybody who wasn’t at the start [of the winning run] but that doesn’t mean we think any less of Dan. Dan is an incredible footballer and we want him to be really successful."
Neil was one of a number of academy products to step up over the course of the season, with Elliot Embleton and Anthony Patterson both making major contributions at Wembley.
“He’s everything that we spoke about in terms of being a local boy who has got everything in front of him to go on and be a really successful player," Speakman said.
"We spoke about Embo, we spoke about Patto. Dan is no different.
“It’s not [just] around the 22/23 season for Dan. It’s around the next eight to ten years. He’s one of our young puppies and what an incredible season he has had.
"He’s playing for his hometown club and he has become a regular in the team. He has contributed on numerous occasions and he’s dancing around on Saturday night with a play-off final winners medal."
Neil signed a new four-year deal in October last year and signalled his intent then to help the club rise back through the divisions.
The midfielder had previously turned down interest from Premier League academies in the hope of making a senior breakthrough on Wearside.
"Everyone knows that I love this football club and I love playing for it," he said at the time.
"It’s a dream come true to be playing in the first team and I’m loving every minute of it, but I want more and I want to be playing in the higher divisions for Sunderland.
"I want to be part of getting this club back to where it belongs and there’s nowhere I would rather be, so I’m delighted to have extended my contract.”