Englishal sums up the attitude of many here:
"Unfortunately at the moment lots of "airspace" is not available to certain aeroplane types, due to performance reasons, qualification reasons and equipment issues"
....and so the proposal by many on this thread is to increase the airspace limitations, introduce additional controlled airspace and mandate increased equippage of kit that may not be suitable for the platform! So, to paraphrase....you don't have, or are unwilling/unable to invest in, the equipment necessary to fly in fully controlled airspace so we want others to spend money upgrading their equipment instead!
As has been pointed out elsewhere, the majority of mid-air collisions, despite rigourous procedures, technology, etc. appear to happen in CONTROLLED airspace. Therefore we need to ensure that the appropriate measures, commensurate with the actual (and not perceived) risks are adopted.
This thread also shows how much there is for us all to learn from each other about how we operate....Everyone is now a little more aware that gliders operate throughout Open FIR between ground level and FL195. Yes they can legally fly in IMC conditions, yes they have an established operating procedure for cloud flying that involves notification through a common frequency (130.4). Very few gliders are transponder/TCAS/Mode-S/ADS-B equipped which means they won't be picked up on the units in power pilots cockpits. Yes they can stay airborne for eight hours plus and fly for hundreds of miles and don't spend all their time within a few miles of the home site. Yes there can be several hundred gliders airborne at the same time. No, many power pilots don't seem to be aware of them.
Here's a quick test - if you fly tomorrow (Sat 30th), see how many gliders you spot on your trip. Then take a look at
Daily Scores in a few days and see how many you should have seen. Then bear in mind that only a small number of pilots put their flights up on the ladder (not everyone is competitive).
Finally, a poster (Rod1?) mentions about introducing something that would undoubtedly help in VFR to reduce the risk...that of proper training AND TESTING of good lookout. When I do a check flight (gliders) with a pilot, lookout is an aspect that I will always be specifically watching out for (pun not intended). If a student pilot flies brilliantly, does a wonderful circuit and exhibits wonderful decision making but does not demonstrate good lookout then I will spend time with them to improve this before I will allow them to fly solo. I believe this to be the case with the other instructors at my club too. The very first lesson that I do with a new student is to stress the importance of lookout. I'd assumed this was the case throughout the aviation community and not just in gliding. Perhaps that isn't the case?