Blizzard has been dealing with criticism regarding Overwatch's role distribution for a while since there are too many damage heroes. This will continue until Overwatch 2, with the DPS heroes remaining prevalent in the original.
Overwatch teams tend to have issues when it comes to compositions due to too many players preferring damage dealers over tanks and supports. While damage roles are usually more popular in any game, the reason for the lack of interest in tanks and supports in Overwatch may be because there aren't enough of them.
The choice is so limited that the number of DPS heroes alone outnumbers the number of tanks and healers combined. Echo is the 32nd hero to be introduced to Blizzard's shooter and 17th damage dealer. It's not hard to do the math from those numbers alone as the remaining 15 heroes can be further divided into eight tanks and only seven supports.
Unfortunately, this split between the roles will remain as it is until Overwatch 2 since Echo will be the last hero to be released before the sequel . On the bright side, Jeff Kaplan stated that "there is a big list of supports and tanks in development for Overwatch 2" in the talk with IGN, linked in the previous sentence.
That is encouraging for two reasons. First, maybe having more options when picking tanks and supports will prompt more players to try those roles, which could potentially help with the role queue troubles since there are too many damage dealers waiting for a game at any given time these days.
The second reason is that Blizzard already confirmed that all heroes from Overwatch 2 will also be available in the original game and the two will share the PvP matchmaking pool. Therefore, the new tanks and supports will not be locked behind a paywall, which is always good to hear.