It depends on where the particle board comes from. If it’s from good solid wood pieces being ground up to be glued together, then yeah I’d agree that’s wasteful.

If it’s from wood that isn’t otherwise usable (like scraps from things made from hardwood, wood that isn’t suitable for making furniture (like too soft), or pieces of trees that are too small, that’s the opposite of wasteful. It can also be a way to effectively use fast turnaround tree farms which IMO is better than logging established trees at an industrial scale.

Edit: looks like I forgot to do this: ).