To a rough approximation, a "smart TV" consists of a computer, laptop-style, connected to the display and speakers.
From various places online, you can buy "scaler" boards that take HDMI/VGA/etc. to whatever interface the panel uses (LVDS is common), i.e. they comprise essentially all the electronics inside a standard non-smart monitor. They are intended for laptop display conversions but can drive much bigger displays too, as long as the interface is the same. That might be an alternative to buying a much more expensive "dumb TV", i.e. buy a smart TV and "dumb it down" yourself!
For example, this particular one is configured for an iPad's display but the sellers usually have other configurations available:
From various places online, you can buy "scaler" boards that take HDMI/VGA/etc. to whatever interface the panel uses (LVDS is common), i.e. they comprise essentially all the electronics inside a standard non-smart monitor. They are intended for laptop display conversions but can drive much bigger displays too, as long as the interface is the same. That might be an alternative to buying a much more expensive "dumb TV", i.e. buy a smart TV and "dumb it down" yourself!
For example, this particular one is configured for an iPad's display but the sellers usually have other configurations available:
https://www.aliexpress.com/item/4K-eDP-HDMI-LVDS-Controller-...