Looks like they shifted gears from where they were originally going to build the stadium. This is going to be a traffic nightmare with the T-Mobile Arena, Allegiant Stadium and now this all in the same vicinity
thenevadaindependent.com

A’s pivot to new site for Vegas baseball stadium, lowering public funding request - The Nevada Independent
The Oakland A's and Bally's Corp. have agreed to a deal in which the team's $1.5 billion ballpark would be built on the site of the Tropicana Las Vegas.