Since we're all on here we can clearly all use computers.
So it is worth contacting local charities, Ebay or its local equivalent Facebay or Freegan or any of the other places to advertise (collect only). Or a local auction house if you have a dining room and chairs. Some charities will take electrical items and get them PAT tested so they're kosher for sale.
Some councils are still running a service where decent stuff you don't need can be sold.
Clearly there are items that can't, like the dratted pre-1988 sofas or those without labels. And very tatty clothes - though presumably for those of us who can get there, there do tend to be rag-banks. Again, worth contacting the council to ask for the nearest or any service that will take them. Anything cotton or woollen I put in my compost heap, but realise not everyone has one.
As for "not enough volunteer staff" for charities - possibly because (a) most young couples are juggling two jobs and children just to afford rent or mortgage (b) more grandparents are doing more childcare (c) more people need to work until they're 67 because of the pension changes. Perhaps the Duke of Edinburgh award scheme and others should make it a qualification to do charity shop working or whatever.