It is possible to create a tracker with channels, samples, instruments, etc. unlimited? ???
Theoretically with OpenMPT it could be possible, altho it's currently capped at 127 channels, not sure how many instruments/samples tho
In the end you are always limited by system resources. Of course you can of course design a tracker in a way that will allow an effectively infinite amount of e.g. samples, but you'd still be limited by how much RAM you have. Also, during playback the tracker has to scan each channel to see if there's anything to play on that channel, so even though you could in theory maybe have a billion channels, your CPU wouldn't be able to process all those channels in time.
But even before reaching those physical limits, there are other questions to answer: How would your pattern look like if you need to support 6-digit instrument numbers. The instrument column would be so wide that in the worst case you can only fit a few channels on the screen.
Last but not least, OpenMPT can currently not support arbitrary amounts of anything because none of the file formats supported by OpenMPT can handle unlimited quantities of anything. There's simply no possibility to use more than 127 channels in IT and MPTM pattern data for example, which is the reason why 127 channels is the maximum in OpenMPT. Supporting more channel, more samples and instruments requires designing a new file format to handle those quantities. But even then, it makes sense to limit these quantities to sensible amounts to keep the software usable due to the constraints mentioned above.
If any composer needs more than 127 in any meaninful way, that's something I'd really love to see!
If I ever get to any more than say ~30 (and those 30 channels includes chunky chords), they are usually doubled up and 'manual effects' that could be easily rendered out separately anyway and superfluous as played real-time.
I'm sure that it can make sense in some situations - maybe not for composing a classic piece of music but rather for arranging sound effects and stuff like that. Still, 127 is indeed plenty and should be sufficient for most people. I don't think I have seen modules really using more than 70 channels in the "final product", but definitely using more channels before finalizing it, for clearer separation and as scratch space. So during the composition process it can be very helpful to have a bit more space than strictly needed. I wouldn't mind OpenMPT supporting more channels - but as mentioned, this is a limitation of its file formats, and I'm not going to introduce a new file format just to have more channels. There are more fundamental limitations that need to be addressed as well.