D&D 5E Low dex wizard

[Baron Opal II]

Has anyone had any experience with not doing this - with instead putting the second highest stat into constitution and planning to accept getting hit more often and just hope to soak it up?

Sure, mage armor, false life, and sleep are your friends. Shield is better at higher levels when you can burn a 1st level spell in a crisis. Mirror image is a reasonable spell pick at 3rd level.

Look at "wall" spells - those that create barriers or zones that the enemy will not wish to cross. That assists your allies as well as protecting yourself.