Trying to book a flight - don't they want my business?

For three days now I have been trying to contact BA. I just want to check seat availability on flights to Miami in November before I book and pay online. I refuse to pay before I know where I'm going to sit! I fly to the US twice a year on BA and never had any problems before but now it's simply impossible to get through by phone. It's an 0844 number which apparently costs 10p per minute from my landline and on getting through I am informed that they are 'experiencing a very high volume of calls' blah blah AND the wait time is announced as anything from 30 mins to one hour!! Work that out!
I eventually decided to try Virgin and that was better - got through in ten minutes but learn that if I book now, I cannot reserve my seat until 60 days before I fly. Why would I buy 2 premium economy tickets costing over £2200, and wait until the appointed day when choosing our seats which will will then amount to a lottery? I can't understand why these major airlines are now giving the inferior service we previously thought was only acceptable from budget airlines. Having said that, I wish Easyjet flew to the US as at least it's possible to book your seat in advance for a small fee. Interested to hear any similar experiences..