Why has nobody made a multistandard digital TV receiver yet?

[Videogamer555]

I know online you can buy multistandard (NTSC/PAL/SECAM) analog TVs for people who travel to different countries a lot, so they can buy one TV and then just use it wherever they go. However most countries now transmit digital TV and have stopped all analog transmissions. So there would seem to be a HUGE market for multistandard (ATSC/DVB-T/IDSB-T/etc) digital TVs. However, unlike in most situations where when there's a need and the market rises to meet it, in this situation the market is not rising to meet this particular demand. In fact, I can't find any company that makes what I'm describing. Are the technologies involved patented such that the wording of the required licenses to get permission to implement any one of these standards, is written in such a way that the license FORBIDS the manufacturer from also implementing any other standard in their TV?

[Subtitles]

Look for Leadstar TV portable TV's.
Also this Konsta TV 12" it has ATSC, DVB-T, DVB-T2, ISDB and Analog TV
There should be other sizes if you do the search
https://www.alibaba.com/product-detail/Full-1080P-Thin-Lcd-Television-ISDB_60745257102...7ec07c51QWQ5VA

[Subtitles]

Making a TV with a multstandard digital TV tuner inside is not attractive to TV makers.
It is a better to make just a basic LCD Monitor (I wouldn't call it a TV if it has no tuner inside) with several HDMI inputs and connect to it an external set top box that has several features.
For example this GTMEDIA Model GT Combo has satellite tuner that supports DVB-S2X, BVB-T2 DVB-C ISDBT ATSC-C(J.83B)
https://www.aliexpress.com/item/1005008659546174.html
I can't say how good this brand is as a set top box, but there are other manufacturers for similar set top boxes.