Italy stunningly missed out on reaching the 2018 World Cup after a 1-0 aggregate loss to Sweden in their play-off, which was completed on Monday.
With Italy needing a goal late in the second leg at the San Siro, De Rossi was asked to warm-up – only for the defensive midfielder to angrily respond by pointing to Lorenzo Insigne to show Italy needed an attacker on the pitch at that moment.
Italy boss Gian Piero Ventura still would not put Insigne into the match, but Low was full of praise for the 34-year-old Roma midfielder for his response.
"I read yesterday that De Rossi said he wouldn't want to be subbed in, because they needed a striker. For me that is greatness," Low said after Germany's 2-2 friendly draw against France on Tuesday.
"So I think it's a little sad for Italy. I would've been happy if the Italians were part of [the World Cup]."
Low said the absence of the four-time world champions, who failed to qualify for the first time since 1958, was a huge blow to the showpiece tournament.
"We can't influence the draw. Everything can happen. In Italy's case, I congratulate the Swedes. I saw the game, they defended well and gave everything," Low said.
"But I think it's sad for Italy, because for such a big tournament [it's a pity]. If Germany or France or even Brazil or Argentina [miss out], for me there is something missing without the Italian team.
"It's also sad that Chile isn't qualified, they didn't manage it. For Italy though it is kind of a chance for a new beginning. Some of their players are ending their career.
"I have the biggest respect for those players, that played not only for Juventus, but also those that played in the national team. Gianluigi Buffon – biggest respect. [Leonardo] Bonucci or also De Rossi or the others. That's pure class."