Again, I rarely encounter .odt documents, but the few I got worked reasonably well for me. So, from my point of view, TextMaker is not "substandard"; it's the standard I measure other word processors at. TextMaker is one of the few apps I couldn't do without, and If I were ever forced to give it up and adjust to some other word processor it would be a serious blow to me.
All this may be completely different for somebody else. SoftMaker didn't develop PlanMaker and Presentations because they wanted a "real" office suite at any price, but because many users cried for it and made it a point of buying or not. Companies set their priorities just as users do. As a customer, I consider myself my own company and choose according to my needs. My needs are satisfied best by TextMaker. If your work and your projects are of a kind that lets you run into the limitations of TextMaker and ultimately decide for OOo Writer as best suited app for your needs, that's the way it is. I can understand if you are disappointed or even slightly infuriated because TextMaker doesn't meet your expectations, and of course I would also like to see it still better than it is now, but from my experience the SoftMaker people have done an excellent job so far.