https://www.espn.com/nhl/story/_/id/28655061/is-alex-ovechkin-nhl-greatest-goal-scorer-ever
This will be heresy to my generation of hockey fans. But, yes, Ovechkin has a strong case to make for being the greatest goal-scorer of all time, surpassing Wayne Gretzky. If he's not there yet, he should get there by the time he retires. I'm not a Caps fan or an Ovechkin fan. But still! Here's the case for Ovechkin:
As the article notes, Ovechkin is about to reach 700 goals, and has a good chance of surpassing Gretzky's 894 by the time he retires. If he doesn't, he should at least get close.
Gretzky played in the highest-scoring era in modern NHL history. When Gretzky was at his peak in the 1980s, the average NHL team scored about 25-30% more goals than it did during Ovechkin's career (which is the lowest-scoring era in many decades). If you make a 25% era adjustment to Ovechkin's total, he's already up to about 870 goals, and he's likely to have several more good years left.
Gretzky had way more help. On the 1980s Edmonton Oilers, Gretzky was surrounded by all-time great offensive players like Jari Kurri, Paul Coffey, Glenn Anderson, and Mark Messier. Ovi's teammates fell far short of this standard, in most years. As a result, opposing defenses couldn't key on Gretzky as much as they could (and did) with Ovechkin. In addition, the 1980s Oilers played a wide-open style that, combined with the nature of the era, tended to maximize goal-scoring. The Ovi-era Caps generally aren't like that.
Ovechkin faced tougher competition. During his career, all or nearly all the world's best players were in the NHL. In the 1980s, by contrast, that wasn't yet true - thanks in large part to the fact that the Iron Curtain was still closed, which meant only a few defectors got to play in the NHL.
However, even if Ovechkin deserves to be considered the greatest goal-scorer, Gretzky is still the greatest all-round offensive player, by a large margin:
In addition to the 894 goals, Gretzky also posted an unthinkable 1963 assists. That's more assists than any other player has total POINTS (Jaromir Jagr is a VERY distant no. 2 with 1888 total points). Ovi only has a comparatively paltry 570 assists. Even accounting for era differences and the quality of the supporting cast, he doesn't do anywhere near as much as Gretzky did to create opportunities for teammates. In fact, in this respect Gretzky pretty much dwarfs every other hockey player who ever lived.
I won't run the numbers. But Gretzky has a substantially superior playoff record to Ovi, even though the latter's is still very good (it wasn't his fault the team only won the Cup once during his career; the supporting cast was principally to blame).