Thank you for the opportunity to help you with your question!
One thing to understand is that when crossing over don't happen two things occur, two things occur genetic variation will be limited to only
independent segregation , and random fertilization. And without crossing over, the composition of chromosomes will not
I think these would be the consequences,
1. The genetic variation among individuals of future generations will be largely restricted
2. Being genetically similar it will wipe out the number of population thus leading to higher risk of extinction of the population
Please let me know if you need any clarification. I'm always happy to answer your questions.