We can simply look at the last downturn, which took place only seven years ago or so. Having worked for an open source company back then, it was most definitely not a time of opportunity. The company managed to survive, but salaries were cut for everyone, very few people were hired and investments were nearly impossible to get.

Maybe it was even worse for people working in Java or .Net, maybe not (many of them do government work etc which is less affected by the market) but it was certainly not a boom time for anyone.