Smart TVs are the worst. Unrelated to TLS: I work for a video streaming company, and while almost all of desktop/mobile Chromium-based traffic is Chrome v80+ or at least v70+, the smart TVs have webviews based on Chromium v45~55 (most TVs) or ~v60 (cutting edge modern Samsungs), and some older ones (~2016) are even worse, based on a very outdated webkit which is more or less Safari 8.0 - basically hardly better than IE11.
But coming back to TLS again: even if the old devices have an up-to-date root store, they typically have an outdated TLS stack which does not support TLS 1.2 ¯\_(ツ)_/¯ and this one is probably even harder to update. And since most of the companies want to drop TLS 1.1- support on their servers soon, this should also doom those outdated devices apart from the root stores issues.
If this is the newspaper-whack-to-the-nose that gets people to stop using sly TVs as more than dumb monitors, then I think we'd all be better off for it.
But coming back to TLS again: even if the old devices have an up-to-date root store, they typically have an outdated TLS stack which does not support TLS 1.2 ¯\_(ツ)_/¯ and this one is probably even harder to update. And since most of the companies want to drop TLS 1.1- support on their servers soon, this should also doom those outdated devices apart from the root stores issues.