How exactly did them using common practice say "We made our version of that game better than them"? I reiterate, you are making something out of nothing. Obsidian are not concerned with what Bethesda does. This is just the internet making faux flame wars. Imagine Fallout 76 was good and well received. The same people that are convincing themselves that this is a dig would be accusing Obsidian of riding on Bethesdas coat tail whereas the reality of the situation is just developers using common practice.

Also in what world is this first person, retro sci-fi open world similar to the isometric fantasy of Pillars of Eternity? Of course Obsidian are going to push their Fallout credentials as its the most similar type of game. Its why say Insomniac would say "From the makers of Infamous" while advertising Spiderman instead of "From the makers of Resistance Fall of Man". The only "dig" Obsidian made is in peoples head.

Mountains out of molehills.