It is a defensive game you gonna have to learn to play like them lol.
Why do people keep saying it's a defensive game? What do you define as defensive? Camping, sitting in shield, or spamming rolls? Those are all punishable one way or another, and sometimes online makes them harder to punish, but it's the players choice to play online and adapt to input lag no matter how much. From my experience, however, I feel Sm4sh's online has made a significant improvement, and I only occasionally have bad but tolerable input lag.
Though I play a majority of FG which is either full low level/causal players, players who lack game knowledge, or the occasional decent player. (Rarely a good player)
A player can work around defenses easily if they know how to. I'm an aggressive player, not a defensive player. Hence what I said in my above post.
Grab counters shield. Spacing can potentially spare you of a shield grab or punish.
Rolls can be baited and punished if they are repetitive or not mixed up, and if you can't hit a smash attack on them, get them off stage and/or KO them with a kill move other than a Smash attack.
It's really annoying to hear people say this is a purely defensive game, when it's not.
Everyone also runs and jumps and you don't see people complaining about that.
Safer play is necessary online because people's internet sucks and isn't fully reliable, and thus you have a significant risk of failing aggressive play due to a sudden packet lost or spike in ping. This isn't an issue in person, and most of the top characters in the game favor an aggressive playstyle.
To be fair, defense isn't total trash in this game like it is in Melee and 64, and as long as it's a valid option, there will always be people who insist the game boils down to defense (it doesn't), or plays like a total campfest (depends on the character).
From my experience, ping is actually fixed once you enter a match. Correct me if I am wrong, but I've had matches where I had a great connection, then one match, horrible input lag, but it never ceased, and seemed to be, if not consistent, roughly the same amount of input lag throughout the match. Then, next match (same person) it's gone.
Perhaps I have no idea what I'm talking about and Ping/Input Lag are not related in any way. (This is how League of Legends works anyways)
The only thing I've seen change during a match is the Frame Rate.