National polling is meaningless in an election with the Electoral College.
That depends on the question asked. I started posting weekly national FiveThirtyEight poll summary results here, acknowledging that national polls and Electoral College results are two different things. My purpose in posting the weekly national results was -- and still is -- to provide a handy quick reference we can use to gauge the accuracy of the national polls after all Election Day votes are counted.
If you are asking do the national polls indicate who will win the Electoral College vote, that is a different question, and I agree with your point. It is exactly as you say it is. "National polling is meaningless in an election with the Electoral College."
To answer that question, we can still test the accuracy of the polls by doing what I suggest above, but it must be done state by state, with an eye on the number of Electoral College votes each state has.
Asking the Electoral College question raises the need to clearly define the question. Do you look at all states? Just the top 10 or top 20 "big" states? Battleground states (whatever that means)? Swing states (whatever that means)? That's not a serious problem. It just requires one to clearly define the question before looking for the results.
That said, let's take a snapshot glimpse at 13 so-called "battleground states." Data from FiveThirtyEight as of 10/23/20:
STATE (# of Electoral College votes) FiveThirtyEight Poll Summary
AZ (11) Biden +3.5
FL (29) Biden +3.8
GA (16) Biden +0.9
IA (6) Biden +1.0
MI (16) Biden +8.0
MN (10) Biden +7.9
NV (6) Biden +6.6
NH (4) Biden +11.5
NC (15) Biden +2.9
OH (18) Trump +1.0
PA (20) Biden +6.1
TX (38) Trump +0.5
WI (10) Biden +6.6
Same exercise using RealClearPolitics reports of most-recent state polls:
AZ (11) Biden +1.0, +3.0 (two polls same day)
FL (29) Biden +1.0, +5.0 (two polls same day)
GA (16) Tie
IA (6) Biden +3.0, +3.0, Trump +1.0 (three polls same day)
MI (16) Biden +12.0
MN (10) Biden +6.0
NV (6) Biden +2.0
NH (4) Biden +10.0
NC (15) Trump +1.0
OH (18) Trump +3.0
PA (20) Biden +7.0, +5.0, +8.0, 10.0 (four polls same day)
TX (38) Tie
WI (10) Tie, Biden +5.0 (two polls same day)
There are 538 votes in the Electoral College. 270 are needed to win. By number of Electoral College votes, the 13 largest Electoral College vote-states are listed below. Combined, these states would command the majority win if they all voted the same way. Poll summaries shown are from FiveThirtyEight as of 10/23/20.
STATE (# of Electoral College votes) FiveThirtyEight Poll Summary
CA (55) Biden +29.7
TX (38) Trump +0.5
FL (29) Biden +3.8
NY (29) Biden +30.9
IL (20) Biden +17.3
PA (20) Biden +6.1
OH (18) Trump +1.0
GA (16) Biden + 0.9
MI (16) Biden +8.0
NC (15) Biden +2.9
NJ (14) Biden +20.2
VA (13) Biden + 12.1
WA (12) Biden +24.3
Trump is not without his strong states but those states have a smaller number of Electoral College votes.
Trump's Top 10 States (ranked by RealClearPolitics poll summaries as of 10/23/20:
STATE (# of Electoral College votes) FiveThirtyEight Poll Summary
AL (9) Trump +17.8
AR (6) Trump +18.1
ID (4) Trump +19.8
IN (11) Trump +10.2
KY (8) Trump +17.5
MS (6) Trump +14.8
OK (7) Trump +21.7
TN (11) Trump +13.4
WV (5) Trump +24.3
WY (3) Trump +37.3
Total Electoral College votes in Trump's top-10 states: 70
Biden's strong states also include some states with a smaller number of Electoral College votes.
Biden's Top 10 States (ranked by RealClearPolitics poll summaries as of 10/23/20:
NY (29) Biden +30.9
CA (55) Biden +29.7
HI (4) Biden +32.2
DE (3) Biden +25.6
DC (3) Biden +87.0
MD (10) Biden +32.1
WA (12) Biden +29.3
MA (11) Biden +38.4
VT (3) Biden +33.2
RI (4) Biden +32.2
Total Electoral College votes in Biden's top-10 states: 134
We can slice and dice the data for all kinds of Electoral College scenarios. However way you slice it, the state-by-state polls show Biden holds the Electoral Cololege advantage, as of today.