1) Yes because this is in ANY way remotely similar to a raid. We were told special items would be available at random times when they first told us about remnant vendors. Live with it. I like the system as do a few others.
2) I do understand and your 1/2 year is again WAY off base. Try being a little more realistic next time instead of making up numbers. The crown of fire was available for ONE week when remnants were first introduced. Less then a month or 2 later it is AGAIN available...so tell me again how that is 1/2 a year? This is ALL we have to go off of for the bracer/cloak so it might be available again in a month or 2...not 1/2 a year.
I personally like the system. I like how it changes. I hope they leave the upgrade for the bracers/cloaks on the vendor but limit the availability of the bracers/cloaks to every few months. They told us the bracers/cloak item would be available in the near future when they wanted feedback on items specifically designed for remnant vendors and they did what they said. You had PLENTY of time to save up your remnants or do what other people do and farm. Stop whining because you can't afford them because you chose not to do either.