The blocker now is getting brain preservation equipment in every hospital; we already have techniques that will preserve brains for centuries until uploading tech is perfected.

See the BPF's article [1] or video series [2] if you prefer.

[1] https://www.brainpreservation.org/wp-content/uploads/2018/02...

[2] https://www.youtube.com/watch?v=v2scSuw0om8

Disclosure: I volunteer for them.