I wouldn’t be so hasty, the Anthem is an excellent bike in all other respects and mine is been fine in all kinds of mud on established trails.
My problem was encountered on freshly mown single track with remaining grass, nettle stalks and other debris that had gone from dry in the morning to a clay like substances are a couple of rain showers. Its pretty unique. Its been fine in a wet Wales and in the winter bog in my local Woodsy (established) singletrack. If it had continued raining I would have been fine. Further examination of my tyre choice yesterday reveals only about 3mm clearance around the seatstay bridge and chain stays, so you can see the issue.
I’ll be going to a Rocket Ron (Smaller, better mud shedding) as my normal tyre of choice from now on until I can find a 2.1 Ralph for next summer rather than the 2.25 I have in there now. Possible also exaggerated by the wide rims I have on there.
I will from now on take my spare wheels mounted with 2.0 beavers should the practise lap reveal I need them.
Add all those circumstances up and et voila…