The quadruple world champion and Mercedes driver started his career at the then-powerful McLaren team.
“I’m sad that they’re so far behind,” Hamilton told Belgium’s F1 Journaal.
“I’m just as sorry that a team like Williams, which I grew up watching, is also not at the front,” he added.
“It’s crazy that the team that had drivers like Nigel Mansell and Damon Hill and won so many world championships is so far behind.
“And I was once in the McLaren family and it’s because of them that I made my debut in formula one. They’ve been having problems for a very long time.”
Hamilton said he hopes the major changes scheduled for 2021, including vastly different technical regulations and a budget cap, helps those teams.
“I really hope there is light at the end of the tunnel for them,” said the Briton.
“No matter what is decided by Liberty Media, I hope that 2021 helps them to put things in order and perform better.”