HI,
I have the same problem as you. Did you menage to fix It? I did not and desperately looking for it.
Thanks.
Regards,
ZV
Link below solved my problem. Hairdryer trick in step 1 allowed me to boot into phone normally long enough to unlock the boot loader and enable usb debugging. Also the second link shows how you can resolve the problem permanently without having to use the hairdryer going forward.
https://www.reddit.com/r/nexus5x/comments/8pbg5n/my_guide_to_fixing_the_nexus_5x_bootloop/
https://www.xda-developers.com/nexus-5x-bootloop-fix-boot-phone/