Expectations were exceeded for Indiana Jones 5's showing at D23. While the guarded speculation was that the title would be announced, this did not come to pass (which makes you wonder if they know it yet), but that couldn't have stung much for the panel's audience when the first footage was debuted to them instead.
Problem is, this sizzle reel was exclusive to the event, so no official upload will be forthcoming, and at this point an unofficial one doesn't seem likely either. You're going to have to make do with writeups of the trailer, such as the one below from The Wrap:
The “Indiana Jones 5” trailer was wonderful, showing a bunch of great moments: Mads Mikkelsen as a Nazi, Indy riding a horse through the New York subway, a chase that takes place in a Manhattan tickertape parade, and Sallah (played, once again, by John Rhys-Davies). We also see Phoebe Waller-Bridge’s character and the trailer ends with Indy getting his whip out and snapping it at a bunch of bad guys, who promptly get out a lot of guns. He ducks.
It looks like it really captures the spirit of the original three films, a spirit that was sadly missing during the most recent installment, “Indiana Jones and the Kingdom of the Crystal Skull.”
What did make it online was footage of James Mangold, Harrison Ford and Phoebe Waller-Bridge on stage before/after the trailer ran. Ford emotionally describes the movie as his last outing as Indy and praises his costar. Here is one capture:
Hey, at least Willow didn't let you down.