In general, the times aren't good for Deception nowadays, I agree.
Top deck info isn't representative, people get a win streak, like, 30 games, 21 win, 70% win rate. It happens especially often when a guy first pushed down to lower ranks on WR and then skyrocketed back to the higher liege. Many decks rely on luck a lot so they sometimes have a long row of wins or losses. Then, the "capable hands" can de-rank again but his lucky deck becomes a monument in top decks table on gudecks.
I agree with you. There is no way to maintain an average based on top ranks. These are collections with a high cost for what they can deliver to the player. While there are simpler and cheaper options like WAR AGGRO.
I understand the win streak argument, but if you look at the matchup tables at https://gudecks.com/meta/matchups?god=deception&timeFrame=7&userRank=10 you'll find the Deception decks that have an overall win rate against other archetypes above 50%. In the case of Solar Gold and counting 7 days worth of matches, Mayday, Hidden Rush and Aggro have win rates above 50%. The latter 2 are generally pretty cheap decks. You don't get these numbers with win streaks only, these percentages take into consideration matches for all players.