We never know how old these videos are.
Because we do see her in public every so often, I don’t buy in to Soused Stepdad’s claim that she’s dead or in captivity, although if she’s faking her own life, that kinda makes her the anti-Scoopy, and I tip my hat to her.
To be fair, the dance videos don’t always seem to take place in the correct season, and Britney’s apparent age and weight seem to fluctuate dramatically from day to day, so I think there’s a lot of recycling going on, and Plastered Pop may have a valid reason to think that there is something behind the curtain. If Britney were actually dead, the person who controls her IG account could claim she is a recluse and could probably cover up her death for years by dipping into the strategic video reserve.