Yeah, it was never in its literal sense but more like "you get the best possible outcome for this action".
For example, if the player is attempting something totally stupid the 20 result might even be "and nothing bad happened", as nothing better was possible (for instance it is impossible to break the one ring with a hammer, so even not totally wrecking your powerful hammer could be a great outcome of such a foolish action).
Or a 20 for asking the eagles for help might be that they bring you half-way, as the eagles wouldn't want to get too close to Mt. Doom anyway.
> Or a 20 for asking the eagles for help might be that they bring you half-way, as the eagles wouldn't want to get too close to Mt. Doom anyway.
I'd also add that ideally (if the DM is fully in the spirit of how this can be played for maximum creative storytelling potential), asking/negotiating for the assistance of the Eagles wouldn't be a single quick dice roll, but rather a complex, possibly hour-long session of courtly intrigue, diplomacy, and politicking, featuring many dice rolls, a lot of carefully chosen words, and a lot of favor-trading and maybe even intimidation. Ideally, getting straight to Mt. Doom via the Eagles should really be achievable, but not with just a single roll of a 20 - rather I imagine it would perhaps involve a concerted and creative effort by the whole party during at least an hour of playing time.
And then, there will be numerous dice checks to survive Mordor's anti-air assets (including probably cool eye beam lasers from the Eye of Sauron tower) and to accurately land the ring in the volcano despite buffeting wind. If any of those checks fail and the ring falls into inert dirt, the party would probably have to quickly send a commando team into Mordor to rapidly finish delivering the payload to target before Sauron's mages arrive in overwhelming force. Would honestly be more fun to play through one of these semi-failure disaster scenarios than an easy win!
Even if / when the party defeats Sauron, they don't have to stop there. For example, they could set their sights on investigating and stopping the reason for the waning of magic from the world, or any (ideally noble, or at least villainously entertaining) goal of their choosing. They could even e.g. research and create dimensional travel magic and hop to a totally different setting such as that of Star Wars.
Rather than "destroy sauron's ring", it's more like "you dislodge a mysterious gold coin that was stuck to the bottom of the table".