Until this happens, speed WRs will continue to rule the day disproportionate to their actual skill/OVR. Sliders can minimize this gap (threshold/coverage), but they can't fix it entirely, just mitigate somewhat.
Throwing to a big bodied possession WR with great hands who 'has position' on his man should be a solid decision. In current state, it's likely a WR/DB animation resulting in a drop/knock-out...and besides, somewhere else on the field, a 68 OVR WR with 95 SPD has beaten his 85 OVR DB by 5+ yds. Throw it to him instead. Conversely, running man with a mismatch should usually mean that, a reception... but not a guy open by a mile who RACs for 30+ yds and often a TD.
I'll give EA somewhat of a pass here in that the more realistic coverage gets, the less scoring you'll see. EA has to balance it so 5 min quarters in H2H still result in several TDs, which by definition means a WAY higher % of drives ending in TDs than you'll find in the NFL's 115-140 snap games. To do that you need to make big plays much easier to find, which means you need coverage & pursuit angles to be weaker. If you calibrated NFL-like gameplay to H2H snap counts, you'd have offenses average 7-10 ppg (meaning, many teams only scoring 0-3)... which nobody would find enjoyable. That's a design issue that isn't easy to solve, because "just make it more realistic" isn't the answer we all want it to be.
I just hope at some point they allow longer-quarter players more tools to bring their games more in line with NFL gameplay a la the more realistic coverage/defense that they are clearly capable of developing when they think it'll be fun.