Insiders have previously indicated that we'd be seeing a Battlefield 6 reveal sometime this week, but it's looking like that announcement has been delayed.
Several insiders have claimed that the Battlefiled trailer has been delayed from its expected release of this week to an unspecified date. There are conflicting reasons and reports as to why and when, but the general consensus is that the trailer has been delayed.
Regular Battlefield leaker Tom Henderson commented on the trailer not being released yet and said that he believed it was because of a real-life incident involving a Chinese rocket and its debris falling down to Earth. Tom said, "The rocket in the trailer does explode and falls down and kills soldiers, so releasing the trailer (if a disaster happens) could be a bad move".
The rocket later landed in the Indian Ocean with no one harmed, but it would make sense for EA to hold back on releasing the trailer until the incident is further behind them. It's not confirmed that this is the reason for a potential delay, but it would be a bad look on EA's part.
Jeff Grubb also commented on the lack of a Battlefield 6 reveal, and updated his Game Mess list to account for the delay. A Twitter post from him also said, "I do think that Battlefield moved to later this month/early next month", although no context for the delay was given. Grubb has now updated his Game Mess list to say "May-Juneish" for the Battlefield 6 reveal.
Although Tom Henderson believes that the recent rocket crash is the main reason for the delay, Jeff didn't go into any detail on why we haven't seen Battlefield 6 yet. Tom Henderson famously sketched out scenes from the trailer before leaked screenshots confirmed what he'd been drawing, so it's clear he's pretty linked to the Battlefield reveal.
The only current details we have about Battlefield 6 come from DICE, who revealed that it has its biggest team working on the game and that a reveal would be coming this Spring.