MGM has something of a problem on its hands. If it wants to continue making James Bond films, it is going to have to replace its leading man, Daniel Craig. Craig has made no secret of the fact that after fifteen years, and five movies playing the fictional superspy (including No Time to Die), he is done with the role. It's entirely possible that MGM might be able to tempt the actor back for another showing, but eventually they will have to cast someone new to take over the franchise.
In the older days of the franchise, this wouldn't have even been an issue; leading men just came and went as far as the Bond movies were concerned. While Roger Moore stuck around for an impressive seven films, Timothy Dalton only managed two. Whenever a new actor was needed, they were simply cast and placed into the role without any of the other characters so much as a mentioning that suddenly 007 was looking a bit different.
The problem for MGM is that the Bond movies have become a lot more interconnected than they used to be. Sure there would be recurring characters (such as Felix Leiter or Blofeld), and Tracy Bond was referenced after her introduction and death in On Her Majesty's Secret Service, but these characters were by and large the only way in which the plot carried over from one installment in the series to the next. It was an episodic franchise, and while one director theorized that the different Bonds were different people, that was ultimately just that, a theory.
From Casino Royale onwards however, the moviemakers began making an effort to create a larger story which carried over from film to film. Not only does the ending of Casino Royale lead into the events of Quantum of Solace, but Bond's actions in the latter are entirely motivated by what transpires in the former. Equally, Spectre attempts to tie itself in to Craig's earlier Bond films by having its main villain take the credit for the events of those films. This increased focus on having an interconnected plot means that when Craig does eventually retire from playing 007 for good, it will have a greater impact than when any of his predecessors made the same call, with the exception of Sean Connery perhaps. Luckily for MGM there are a number of options the studio could take to keep the franchise going once it loses its most recent leading man.
The moviemakers could simply decide to replicate the approach of the past, and hire someone without having it be mentioned at all on screen. This approach worked well before, so why fix what isn't broken? If MGM did this it would allow the filmmakers in charge of the next Bond to build on No Time to Die or any of the post Casino Royale movies as much as they liked. The long running, plot heavy series that has defined Bond in the 21st century could be continued without so much as a missed beat. But would they want to? Like somehow managing to get Daniel Craig to agree to do a sixth Bond movie, this would be something of a stalling tactic. Audiences will only appreciate all of the Bond movies attempting to be so closely aligned for so long. Bond himself has already attempted to retire from his job twice, and it might be not be long before the weariness which has been written into the character since Skyfall might start to be apparent in the films themselves. Eventually, the series will need a clean slate if it's going to continue.
The studio might decide instead that a reboot is in order. They could simply decide to go back to having each installment in the franchise only loosely follow one another, and let individual directors decide how much they want to harken back to the movies which came before. Such a decision could be the shot in the arm Bond needs. Future directors would no longer feel like they had to match the tone set by their predecessors, opting instead to make something more uniquely their own. MGM also wouldn't have to worry so much about how much the next actor to play Bond looked like the old one, which sounds silly until one remembers the hue and cry that erupted over Daniel Craig's blonde hair when he was first cast. And if it was decided that the Bond films should return to the plot-heavy approach for a future film, there would be nothing to stop that happening.
But why recast James Bond at all? At this stage do the Bond movies really need Bond to survive? Much was made of the news that in the character's temporary absence, someone else would be taking up the mantle of 007 (played by Lashana Lynch) in No Time to Die. If audiences take to this new character, why not let her continue to lead the franchise? As solutions go it would be the best of both worlds; allowing for future films to be set in the same world which was established by Casino Royale while still giving breathing room needed for those films to establish their own tone and create their own stories without having to justify themselves within the context of Bond's character arc. When Lynch leaves the role, this approach would even come with the option to have yet another character become 007, or return to Bond. Some time away from the character might even make such a return something of an event.
Whatever MGM decides to do, the best way to proceed with the franchise is to realize that Daniel Craig quitting Bond might not be a problem to be worked around. Instead it could serve as an exciting opportunity to reinvigorate the series, and help it stay fresh after so many years.