I don’t even think collecting tsuba is difficult.
Tsuba are plentiful and easily available. Prices can vary from a few $ to many thousands.
However collecting “good” tsuba requires acquiring knowledge and developing the eye that enables you to apply that knowledge…..and the money needed.
…..and what constitutes a “good” Tsuba (and its “$value”) will vary greatly from collector to collector.
Some collect certain artists, certain schools, certain designs, certain periods, certain techniques, certain materials…..there is a huge variety to chose from.….or if you simply want to collect tsuba that simply appeal to you then there is nothing to stop you. Go buy some and see. If you decide it’s not for you then sell them.
You will make financial mistakes (as many of us have) but you will learn from them.
You will make errors of judgement but again you will learn and refine your eye.
If however you want a hobby where you can look up that exact tsuba and ascertain its precise age, maker and price then maybe tsuba are not for you.
I’m sure some of this has been said above already but my attention wandered a bit.