It has nothing to do with ANT+ as Bluetooth Low Energy could also be used. It comes down to the CPU. The only TabA we support uses the Snapdragon 625. I’ve looked up the T290 that you are talking about, and it’s using the Snapdragon 429. If I remember what the android devs said, this is due to the 429 being a weaker CPU. I have the same issue with my Stylo 4, which uses a Snapdragon 425 I think.
Here is a comparison of the two, and there’s some give and take on both sides, but it comes down to the fact that they use the same cores in their CPU’s, the Cortex A53, but the 625 has twice as many cores, and can handle more threads.
Also, even if the device doesn’t have ANT+, you can give Androids ANT+ with the use of a few apps and a dongle, directions can be found here.
Hope this helps!