Yes, even if prices are lower, mortgages won't necessarily be more affordable because of higher interest rates and deposits, even more so if they reduce the valuation and you have to make up the difference or not proceed, tighter lending criteria and insecure incomes.
Buying in a recession isn't a walk in the park. When we bought in the mid 90s, DP got made redundant within about a fortnight, and all that expensive income protection insurance we'd bought wasn't worth the paper it was written on.
A colleague lost 3 purchases due to various difficulties with sellers pulling out because they couldn't afford to move or the valuation was reduced and their deposit wouldn't cover the purchase price. They spent thousands on not buying a house and each time it fell through, it put them back because they had to keep saving to replace fees that they'd lost. Exciting times indeed.
Perhaps if your DH thinks he's so knowledgeable, he should talk to some older relatives who were adults in previous recessions.