Ovechkin had 422 goals in his career as of as of the end of last season. Gretzky had 894.
Ovechkin is 29 years old. Let's say for the sake of argument he plays until he's 40, or up to and including the 2025-26 season (Gretzky played until he was 37). That's another 12 seasons.
Ovechkin is 894 - 422 = 472 goals behind Gretzky. To catch him he would need to average 472/12 = 39.33 goals per season. Let's just round up and say to surpass Gretzky he'd have to average 40 goals per year for 12 more years, including this one.
Is it possible? Yes. Is it likely? No.
By comparison when Greztky was 29 years old he had 677 goals. In his first eight seasons he had 543. In Ovechkin's first eight seasons he has averaged 52.75 goals per season, which is very much commendable. The most Ovechkin has scored in a year is 65.
In Gretzky's first eight seasons he averaged 67.875.
It's quite possible that Ovechkin might do it. If Ovechkin keeps up his current 52.75 goals per season pace he'll pass Gretzky in 2022, but the last time Ovechkin had more than 52.75 goals in a season was five years ago; the average is being dragged down as time goes on...