I agree. I have a network of 3 Deco M9-Plus + 4 Deco M5, both of them supported by the latest BETA versions that were launched in this forum (1.6.1 and 1.6.0 respectively).

Some thoughts:

1) My perception is that the level of product launches vs the level of product support is unbalanced (much more focus to launch and sell new things than to support what has been launched). TP-Link should understand that many sales come from clients that already have TP-Link products. Or from clients that READ this forum.

2) This strategy might be reasonable with stable and bug-free products or with products that are released with most major functionalities available, but it is not case.

3) To make things worse, certain products have different hardware versions under the same model and some of them are supported by different firmware versions, adding extra complexity to clients that cannot access new versions having the same products at home (eg case of Deco M9 Plus, with more than 4 HW versions).  

4) I really appreciate the availability of Beta versions in this forum, but it is really slow these beta versions evolve over time.