I think the issues of high fees has been deal with sometimes ago and we are surpose to have low fees even if bitcoin went as high as $100,000. I think by now fees is no longer the problem because bitcoin was made to provide low fees.
Ye,s the problem of scalability have been resolved once we got segwit activated and right now the total number of pending bitcoin transactions to be picked by next block in memory pool is less than 1600 transactions and optimal fee per Kb is 1170 satoshi which is ~4 US cent as per current BTC value. Do we still need to consider that tx fees is stopping bitcoin's rising markets ?
How do we assume that the ATH of $20k was set by tx fees ? I understand OP like due to high fees, there were no new investors and due to lack of new investors bitcoin was struggling to get beyond $20k. But, since 2018 beginning I was not seeing high tx fees, still bitcoin was falling down by failing to attract new investors.
Tx fees was a reason why bitcoin's value was not rising. But, now we got many other problems like whales manipulations and due to those reasons now we are trading below $4k and honestly not thinking about $20k as of now, just $10k also will make me a happier bitcoin investor.