Space X Won’t Fly a Manned Mission to Mars by the End of 2030
medium.com
medium.com
This pessimism of the target timeline seems to be based on the assumption we can't solve problems we already have been working on solving. Considering it took about 12 years to fully develop the Apollo program (from funding to moon landing), I'm pretty hopeful about a 15 year or so window for Mars with today's technology and resources, given we already started years ago.
I'm tempted to stop here. Astronautical navigation in not a matter of distance, but of ΔV.