Lets see if any of the Roon team wades in. In the meantime you may want to look at this discussion for more
about what Roon considers lossy and what the “quality” indicators mean.
Generally speaking anything less than ie. CD quality ie 44/16 is considered lossy, anything above that is considered Hires.
By this definition MQA files are HiRes as even unfolded as they are generally 44/24 bit. However many don’t consider it HiRes unless is 88 or 96/24 or 176 or 192/24 and MQA is not that unti it is decoded. However MQA files are lossy in the sense that they do not preserve every bit of a 96/24 or 196/24 Hires file they discard some of the bits that contain no musical information, that is why some consider it lossy even though it is a higher resolution that CD. Without any decoding you still get CD resolution.
You also need to understand that MQA is more than just compression and that MQA files have been through a process that attempts to reduce problems in the original ADC conversion when the original digital file created which can improve the sound quality even without decoding. If you really don’t want MQA at all you should find non-MQA files as even if you turn decoding off MQA files will have an element of MQA processing in them and are not the same as the original CD or HiRes file even if they are sourced from the same master.
I find as do many others that usually the MQA file is better even without decoding, decoding improves it further. Many others disagree. Try it and make up your own mind.