This is a personality question rather than generalization question.

My friend got married around early 40s and his wife is late 30s IINM. I initially thought he has given up but looks like it is never too late. However his wife is not someone who he has just knew. They had been together in the past but broke up due to LDR perhaps. Somehow things worked for them during covid and now even had a 1 year old baby.

I personally think it would be hard to really know someone from scratch and then see if can proceed to marriage. That would be for 20s and early 30s. If you are reaching late 30s, I think the most probable is getting married to your previous lover, or through match-making where both are seriously looking to get married ASAP.