That looks like a fine TT BTY, as good as many Entry level TT's from the more popular Brands both Vintage and new IMO. Properly set up with a decent cartridge it may sound Better than it has any right too.
I have a BOTL Pioneer TT from the mid 70's that has the same problem you have. Only when I bought it used it did Auto Return, Now I must press the Return Button to get it to Function.
My guess is it should Auto Return. It may be that a small lever or Sliding part that is getting hung up on dust preventing the auto return Function. While I really don't care myself, If you want to get it going, Remove the platter and lighty clean, perhaps with bottled air any exposed parts, Perhaps lubricate pivot points and sliding parts with a Silicone spray Lube. If they appear to be oiled or greased, use that.
Also while turning the Spindle by hand, watch carefully what happens when you press the Auto Return Button, and when you slowly bring the Tonearm to Center. You might get lucky and see where the problem is. This worked for me when my TT would auto return as soon as it started. The problem might be underneath the Tonearm, which is more involved.